Treatment entry barriers among California’s Proposition 36 offenders

Abstract

To explore why some Proposition 36 offenders do not enter drug treatment, we analyzed self-reported and administrative data to compare the characteristics, perceptions, and re-arrest rates of 124 untreated and 1,335 treated offenders assessed by thirty sites in five California counties. Offenders were comparable in many domains at assessment, however untreated offenders were younger, not employed, more criminally severe, and less motivated for treatment. To avoid incarceration was the primary reason for choosing Proposition 36, but fewer untreated offenders felt treatment-ready (12.9% vs. 35.7%) and more accepted the Proposition 36 program only upon recommendation by others (37.9% vs. 11.7%). Reasons for not entering treatment included re-arrest (31.6%), no desire for treatment (23.9%), and assignment to a program that was too far away (11.1%). Both groups had fewer total arrests after assessment, but recidivism was higher among untreated offenders. Understanding untreated Proposition 36 offenders can aid efforts to improve treatment entry rates and related outcomes.

Introduction

Representing a significant change in criminal justice policy, California’s voter-initiated Proposition 36 set aside $120 million annually to provide community-based treatment to drug offenders who would have otherwise not received it. Proposition 36 has been criticized as “drug policy by popular referendum” (Marlowe et al., 2003) and touted as one of the few correctional reforms to have been fully implemented this decade (Ehlers & Ziedenberg, 2006). To enter treatment under Proposition 36, first eligibility determination is made based on the offender’s current offense and past criminal history, after which eligible offenders are offered treatment in lieu of routine criminal justice processing, and offenders who choose to participate are ordered to complete a treatment assessment and then enter treatment. Participants who successfully complete the Proposition 36 program can have expunged the criminal arrest and conviction that made them eligible for the Proposition 36 program.

Two provisions of Proposition 36 have remained controversial since its inception. First, drug treatment under Proposition 36 must be offered to any individual who meets the offense-based eligibility criteria (i.e., conviction of a nonviolent drug offense like possession of an illegal drug or being under the influence), regardless of drug problem severity, program suitability, or personal motivation level (for more detail on eligibility criteria, see Longshore et al., 2005). Critics contend that the “wide net” cast by Proposition 36 means that people who do not have a drug problem and those who accept treatment disingenuously simply to avoid immediate incarceration waste scare resources that would be better spent elsewhere. Second, Proposition 36 participants who violate conditions of the program (e.g., no-show to treatment, test positive for drug use) or are re-arrested for a new drug-related offense do not face immediate criminal justice sanctions, but are instead legally entitled to three chances to succeed in treatment, i.e., “three bites of the apple,” (Klein et al., 2004). In effect, Proposition 36 increased the number of criminal offenders accessing California’s drug treatment system (Longshore et al., 2005; Hser et al., 2007), many of whom were treatment-naïve individuals with multiple and complex problems that were unexpectedly severe (Hser et al., 2003; Wiley et al., 2004). One concern expressed by stakeholders was whether the treatment system could successfully engage the Proposition 36 client population, especially the proportion that ostensibly was unmotivated to take advantage of opportunities provided by treatment (Hardy et al., 2005).

Since Proposition 36 began in 2001, approximately 50,000 people have been referred to drug treatment annually and of these most are assessed (85%) and two-thirds (75%) actually enter care (Longshore, Urada, Evans et al., 2004). The drop off that occurs prior to treatment entry means that about 25% of all referrals go untreated, comprising a significant minority of approximately 75,000 individuals over the six years of Proposition 36 implementation. Information on treatment no-shows is limited, differences in offender characteristics between treated and untreated individuals have not been examined, and reasons for not entering treatment are unknown.

What little is known about untreated Proposition 36 offenders is provided by UCLA’s statewide evaluation reports. Specifically, more than half of untreated individuals were re-arrested within 30 months of committing the offense that made them eligible for Proposition 36 (Longshore et al., 2006) and 35% reported drug use one year after their Proposition 36 assessment, significantly more than the 27% of those who entered treatment but dropped-out before completing it (Longshore et al., 2005). Curiously, however, compared to those who entered but did not complete treatment, fewer untreated individuals recidivated (Longshore et al., 2005), untreated individuals made greater employment gains one year after assessment (Longshore et al., 2005), and untreated individuals actually cost taxpayers slightly less money, primarily because of lower costs related to arrests, convictions, healthcare, and probation supervision (Longshore et al., 2006). These seemingly discrepant findings raise the question articulated by Longshore et al. (2006): are untreated Proposition 36 offenders primarily low-level drug users who truly do not need drug treatment or are they savvy drug-using offenders manipulating the system to avoid immediate criminal justice sanctions?

This article focuses on individuals who accept Proposition 36 and complete the assessment process but do not go on to actually enter treatment. We address the following research questions: (1) how do untreated and treated Proposition 36 offenders differ in characteristics, problem severity, criminal history, and motivation level? (2) do the reasons for choosing Proposition 36 differ for untreated compared to treated offenders? (3) why do some Proposition 36 offenders complete their assessment for treatment but do not go on to actually enter treatment? (4) is the recidivism rate different for untreated and treated Proposition 36 offenders? We hypothesized that untreated Proposition 36 offenders, compared to their treated counterparts, would be more criminally severe, have a less severe substance abuse problem, and demonstrate a lower treatment motivation level. Furthermore, we expected untreated offenders to indicate that they chose the Proposition 36 program simply to avoid incarceration and that untreated offenders would attribute treatment no-show to not having a substance abuse problem. Finally, we expected untreated offenders to have a higher re-arrest rate than treated offenders.

Proposition 36 is maturing into an established criminal justice diversion option for drug offenders in California. Understanding offender attitudes and perceptions of the program as well as barriers to participation can help stakeholders appropriately modify Proposition 36 to improve its effectiveness.

Methods

Data analyzed in this study were derived from "Treatment System Impact and Outcomes of Proposition 36 (TSI)," a NIDA-funded multi-site prospective treatment outcome study designed to assess the impact of Proposition 36 on California’s drug treatment delivery system and evaluate the effectiveness of services delivered. Thirty treatment assessment sites in five counties were selected for participation based on geographic location, population size, and diversity of Proposition 36 implementation strategy (see Hser, Teruya, Evans et al., 2003 for additional information). County assessment center or treatment program staff collected data from all Proposition 36 participants assessed for treatment in the selected counties during 2004. A sample of participants who had completed the intake assessment was randomly selected for follow-up by telephone with UCLA-trained interviewers at three-month post assessment. Participants were paid $10. Additionally, arrest histories were acquired on all participants from the California Department of Justice. The Institutional Review Boards at UCLA and at the California Health and Human Services Agency approved all study procedures.

Of the 1,588 targeted, 1,465 completed the 3-month follow-up interview, 48 were incarcerated, and 3 were deceased. The interview completion rate was 95% (the deceased and incarcerated were excluded from the interview pool). Comparisons between those who completed the interview and those who did not complete the interview revealed no statistically significant differences in all variables examined (county, treatment modality, age, race/ethnicity, marital status, employment, lifetime arrest, and primary drug problem) except for gender. More females (30% vs. 20%) were in the follow-up completion group than in the non-completion group.

At the 3-month follow-up interview, participants were asked “Did you actually enter drug treatment under Proposition 36?” and those who said “No” (n=124) were categorized as “untreated” and those who said “Yes” (n=1,335) were categorized as “treated” (another 6 individuals did not answer this question and were excluded from analyses).

Instruments and measures

Baseline assessment included the Addiction Severity Index (ASI), a structured interview that captures demographic information and also assesses problem severity in seven areas: alcohol and drug use, employment, family and social relationships, legal, psychological, and medical status (McLellan et al., 1980; 1992). A composite score can be computed for each scale to indicate severity in that area; scores range from 0 to 1 with higher scores indicating greater severity.

Treatment motivation was measured at baseline and 3 months later with the Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES), which assesses readiness for change among drug and alcohol abusers (Miller & Tonigan, 1996). The version of the SOCRATES used in the TSI study was 8D, a 19-item questionnaire for drug and alcohol clients. Treatment motivation was measured by an overall total score and by three sub-scales: problem recognition (alpha=.91) measures patients’ self-assessment of drug use problem, desire for help (alpha=.83) assesses transition from a general acknowledgment of a drug problem to the individual's recognition of his or her need for help and, readiness for treatment (alpha=.63) assesses willingness to enter and comply with treatment, and represents the completion of the above transition and the beginning of the action stage.

Perceived coercion was measured at baseline and 3 months later with 5 items directly assessing desire for treatment and voluntary interest in the treatment program (Monahan et al., 1995). Farabee, Shen, & Sanchez (2002) developed a weighting scheme for these items and demonstrated superior predictive efficacy and a Cronbach’s alpha of .80. For this analysis, perceived coercion (range 0–5) was scored such that a higher value indicated a greater level of perceived coercion.

Proposition 36 offender attitudes and beliefs

Reasons for Proposition 36 program participation

At the 3-month follow-up interview, participants were asked “Why did you decide to accept Proposition 36?” Responses were coded into 8 categories.

Barriers to treatment entry

At the 3-month follow-up interview, untreated offenders were asked, “Why did you not enter treatment?” Responses were coded into eleven categories.

Outcomes

Recidivism was calculated using arrest history records acquired from the California Department of Justice on all individuals. Arrests that occurred 12 months before and after assessment for Proposition 36 treatment were analyzed.

Statistical Analyses

Differences between untreated and treated groups in characteristics and history of substance abuse, treatment, and criminal involvement at intake as well as the individual reasons for accepting the Proposition 36 program were compared by using Pearson chisquare test (or the Fisher’ exact test for small cell sizes) for categorical measures and the two-sample Student’s t test (or Satterthwaite’s t test when the homogeneity of variance was rejected) for continuous measures. For perceived coercion, treatment motivation, the two-sample t test and matched-pairs t test were first used to investigate differences between treatment groups (untreated, treated) and across assessment times (intake and follow-up). Then a generalized estimating equations (GEE) model with identity link function was used to investigate the within-subject assessment time effect and the between-subject treatment group effect as well as their interaction effect, after controlling for differences in age, gender, ethnicity, employment status, age at first arrest, and lifetime arrests. Similarly, for arrests before and after Proposition 36 assessment, the Pearson chi-square test (Fisher’s exact test if applicable) or McNemar’s test were first used to investigate differences between treatment groups or across assessment times separately. Then a GEE model with logit link function was used to test for main effects and interaction effects, controlling for the same covariates mentioned above.

Results

Untreated Proposition 36 offender characteristics

As shown in Table 1, untreated and treated Proposition 36 offenders were similar on many characteristics at assessment. For both groups: the majority was White, followed by Hispanic, and African American; about one-third was female; average years of education was 11; most had never married or were widowed/separated/divorced, and; very few were homeless. The ASI severity index revealed no significant differences between the two groups in all seven domains measured. However, notably, untreated individuals were younger (35.0 vs. 37.1), and fewer were employed (28.9% vs. 39.6%) at assessment.

Table 1.

Characteristics of Offenders at Proposition 36 Assessment

	Untreated (N=124)	Treated (N=1,335)
Age, Mean (SD) *	35.0 (9.6)	37.1 (9.8)
Race,%
White	42.7	51.3
Hispanic	29.0	24.5
Black	20.2	18.1
Asian/Pacific Islander	3.2	2.0
Other	4.8	4.2
Women, %	34.7	28.8
Education, Mean (SD)	11.6 (1.9)	11.8 (1.9)
Marital status, %
Married	11.6	15.7
Widowed/separated/divorced	31.4	35.9
Never married	57.0	48.5
Employed (full- or part-time), % *	28.9	39.6
Homeless, %	10.6	8.4
Addiction Severity Index Composite Score, Mean (SD)
Alcohol	0.09 (0.19)	0.10 (0.18)
Drug	0.14 (0.11)	0.13 (0.11)
Employment	0.76 (0.27)	0.71 (0.29)
Family	0.14 (0.19)	0.16 (0.20)
Legal	0.26 (0.17)	0.26 (0.18)
Medical	0.24 (0.32)	0.24 (0.33)
Psych	0.19 (0.23)	0.17 (0.21)

^*p <0.05.

A nonparametric Wilcoxon-Mann-Whiteney test on all comparisons assessed by the t-test verified results

There were no differences between the two groups in drug use history and prior treatment experiences (Table 2). For untreated and treated offenders, methamphetamine (44.6%; 52.6%) was the most common primary drug problem, followed by cocaine (18.2%; 12.2%), marijuana (18.2%; 13.5%), heroin (8.3%; 10.0%), and alcohol (6.6%; 9.0%). Most had used drugs within the prior 30 days (73.6%; 69.4%) and few lived with an alcohol or drug user (10.7%; 15.8%). For both groups, most had tried treatment for alcohol or drug abuse before (65.3%; 66.6%) and one-third had recently attended self-help groups.

Table 2.

History of Substance Abuse, Treatment, and Criminal Involvement at Proposition 36 Assessment

	Untreated (N=124)	Treated (N =1,335)
Substance Abuse and Treatment
Primary drug, %
Methamphetamine	44.6	52.6
Cocaine	18.2	12.2
Marijuana	18.2	13.5
Heroin	8.3	10.0
Alcohol	6.6	9.0
Other	4.1	2.7
Age at first drug use, Mean (SD)	20.1 (9.3)	20.1 (7.7)
Used any drug in past 30 days, %	73.6	69.4
Lives with alcohol/drug user, %	10.7	15.8
Prior treatment for alcohol/drug abuse, %	65.3	66.6
Attended self help groups in past 30 days, %	29.3	36.1
Criminal Involvement
Age at first arrest, Mean (SD) *	19.5 (6.2)	21.0 (8.1)
Arrested in the past 30 days, % *	46.3	32.8
Incarcerated in past 30 days, % **	60.3	45.6
# of lifetime prior arrests, Mean (SD)*	12.0 (18.0)	8.7 (11.2)
# of lifetime prior convictions, Mean (SD)	5.1 (6.2)	5.2 (6.6)
# months incarcerated in lifetime, Mean (SD)*	32.0 (35.8)	24.5 (32.2)

^*p<0.05;

^**p<0.01

A nonparametric Wilcoxon-Mann-Whiteney test on all comparisons assessed by the t-test indicated that differences in the age at first arrest and the number of prior arrests over the lifetime were not significant across groups while all other effects remained the same.

Untreated offenders did differ from treated offenders on criminal history and experiences with the criminal justice system. Significantly more untreated offenders had been arrested (46.3% vs. 32.8%) or incarcerated (60.3% vs. 45.6%) in the 30 days prior to assessment, and untreated offenders experienced their first arrest at a younger age (19.5 vs. 21.0), had more lifetime arrests (12.0 vs. 8.7), and had spent more months over their lifetime in jail or prison (32.0 vs. 24.5).

Attitudes and beliefs

Perceived coercion was similarly moderate for untreated (Table 3) and treated (0.66) groups at assessment for treatment (0.63). However three months later, treated offenders reported a significantly higher level of coercion than untreated offenders (0.78 vs. 0.56). Motivation for treatment also varied across groups. Untreated individuals had a lower motivation level than treated offenders at assessment (3.92 vs. 4.09) and three months later (3.59 vs. 3.98). At both time-points, untreated offenders scored significantly lower on subscales indicating problem recognition (3.06 vs. 3.33) and readiness for treatment (4.22 vs. 4.41).

Table 3.

Perceived Coercion and Treatment Motivation at Proposition 36 Assessment and 3 Months Post-assessment

	Intake assessment		3 months Post-assessment
	Untreated (n=124)	Treated (n=1,335)	Untreated (n=124)	Treated (n=1,335)
Perceived coercion c**	0.63	0.66 b**	0.56 a**	0.78 a** b**
Treatment motivation c*	3.92 a* b**	4.09 a* b**	3.59 a** b**	3.98 a** b**
Problem recognition	3.06 a** b**	3.33 a** b**	2.19 a** b**	2.61 a** b**
Desire for help	4.04	4.11 b*	4.07	4.18 b*
Readiness for treatment c**	4.22 a* b**	4.41 a*	3.89 a** b**	4.45 a**

^aSignificant differences between untreated and treated groups (a* p<0.05; a** p<0.01), t test.

^bSignificant differences across time (intake, 3 months post-assessment) for each group (untreated, treated) (b* p<0.05; b** p<0.01), matched-pairs t-test.

^cInteraction effect between time (intake, 3 months post-assessment) and groups (untreated, treated) is significant (c*p<0.05; c** p<0.01), GEE.

A nonparametric Wilcoxon-Mann-Whiteney test on all comparisons assessed by the t-test verified results.

The most common reason for accepting Proposition 36 was to avoid incarceration for both untreated (45.2%) and treated (48.4%) offenders (Table 4). However there were group differences for several other reasons cited. Fewer untreated offenders said that they chose the Proposition 36 program so that they could receive treatment (12.9% vs. 35.7%) and more said that they accepted the program only because they were told to do so by others (37.9% vs. 11.7%) like probation or parole officers (13.7% vs. 4.4%), family or friends (13.7% vs. 2.9%), or an attorney (10.5% vs. 4.4%). Very few people in both groups said that they chose Proposition 36 in order to have the opportunity to expunge their criminal record at a later date.

Table 4.

Offender Reasons for Accepting the Proposition 36 Program

	Untreated (n=124) %	Treated (n=1,335) %
Avoid incarceration	45.2	48.4
Wanted drug treatment **	12.9	35.7
Recommended by others **	37.9	11.7
Probation/parole **	13.7	4.4
Family/friends **	13.7	2.9
Attorney **	10.5	4.4
Court/judge ordered it	2.4	1.5
Chance to expunge record	0.8	1.1
Other	0.8	1.7

^**p<0.01

When untreated offenders were asked about barriers to treatment entry (Table 5), most said they were rearrested and/or incarcerated before they could enter treatment (31.6%) while another 23.9% said they either were not ready for treatment or just did not want help. Others said that the treatment program they were referred to was too far away (11.1%) or that they were told to complete detox or another “pre-treatment” program before entering outpatient or residential care (7.7%). Other barriers included long waiting lists (6.0%), preference for a different criminal justice diversionary treatment program (e.g., drug education or drug court) (3.4%), and dislike of the Proposition 36 assessment process (3.4%). Very few offenders said that they did not enter treatment because the care they needed was unavailable (2.6%), they wanted to keep using drugs (2.6%), they were dropped from the program (1.7%), or other reasons (6.0%) like a preference for incarceration over treatment.

Table 5.

Offender-reported Barriers to Entering Proposition 36 Treatment (n=124)

Reported Barriers	%
Rearrested and incarcerated	31.6
Not ready/didn’t want treatment	23.9
Program was too far away	11.1
Entered “pre-treatment” or detox	7.7
Wait time was too long	6.0
Chose drug court/other CJ program	3.4
Disliked Proposition 36 assessment	3.4
Needed care was unavailable	2.6
Kept using drugs	2.6
Dropped from Proposition 36	1.7
Other	6.0

Recidivism

With one exception, arrest histories 12-months prior to Proposition 36 assessment were similar for untreated and treated offenders (Table 6). Most arrests were drug-related 12–months (82.4% vs. 84.3%) before assessment for both untreated and treated offenders. Regardless of group membership, “other” types of offenses (like vagrancy, public intoxification, vandalism) accounted for approximately half of arrests 12-months before assessment. The percentage of people arrested for violent offenses was also similar across groups. However, significantly more untreated than treated offenders had been arrested for a property arrest in the 12 months before assessment (27.8% vs. 17.3%).

Table 6.

Arrests 12 Months Before and 12 Months After Proposition 36 Assessment

	Before		After
	Untreated (n=124)	Treated (n=1,335)	Untreated (n=124)	Treated (n=1,335)
Total arrests, % c*	91.7 b*	89.3 b**	79.6 a** b*	52.8 a** b**
Violent	7.4	4.5	7.4	4.1
Property	27.8 a**	17.3 a** b**	22.2 a*	12.8 a* b**
Drug c**	82.4 b*	84.3 b**	69.4 a** b*	40.5 a** b**
Other c*	58.3	50.2 b**	58.3 a**	35.9 a** b**

^aDifferences between untreated and treated groups are significant (a*p<0.05; a** p<0.01), Pearson chi-square or Fisher’s exact test.

^bDifferences across time (before, after) for each group (untreated, treated) are significant (b* p<0.05; b** p<0.01), McNemar’s test.

^cInteraction effect between time (before, after) and groups (untreated, treated) is significant (c*p<0.05; c** p<0.01), GEE.

Group differences in arrest rates were most apparent in the time-period period following Proposition 36 assessment with more untreated than treated offenders being arrested for all types of crimes. For example, compared to treated offenders, significantly more untreated offenders were arrested 12-months after assessment for property (22.2% vs. 12.8%), drugs (69.4% vs. 40.5%), “other” (58.3% vs. 35.9%) and overall (79.6% vs. 52.8%). Violent arrests were also higher for untreated people (7.4% vs. 4.1%) in the same time period but this difference was not statistically significant.

From assessment to follow-up, arrests decreased among treated offenders in all areas. Total arrests decreased 36.5%, from 89.3% twelve months before assessment to 52.8% twelve months after assessment. The most dramatic decrease occurred in offenses related to drugs, followed by “other,” property, and violence.

By the twelve-month assessment, arrests in all categories either remained the same (violent and “other”) or had decreased among untreated offenders however the magnitude of decrease was significantly smaller than was evident for treated offenders in total arrests, (e.g., a decrease of 12.1% vs. a decrease of 36.5%), and offenses related to drugs (13.0% vs. 43.8%), and “other” (0% vs. 14.3%). Also, for untreated offenders the greatest decrease in arrests occurred for drug-related offenses (13.0% from 82.4% to 69.4%), but unlike treated offenders, the next greatest decrease occurred for arrests related to property (5.6%), not “other” offenses, followed by no change in both violent and “other” offenses.

Discussion

In response to our first research question, comparing the characteristics of untreated and treated Proposition 36 offenders at assessment, we found that untreated offenders were younger, fewer were employed, their first arrest occurred at an earlier age, they had more frequent interactions with the criminal justice system (as indicated by arrests and incarcerations over the lifetime and prior 30 days) and lower treatment motivation levels. Regarding our second research question, do the reasons for choosing Proposition 36 differ for untreated compared to treated offenders, we found that offender attitudes and perceptions of the Proposition 36 program varied across the two groups. Both untreated and treated offenders most commonly chose Proposition 36 in order to avoid going to jail or prison, however fewer untreated people felt ready for treatment and more of them accepted the Proposition 36 program only because it was recommended to them by friends, family members, or criminal justice agency representatives. In response to our third research question on why some Proposition 36 offenders complete their assessment for treatment but do not go on to actually enter treatment, we found that the top three reasons untreated offenders gave for not entering treatment were re-arrest, no desire for treatment, and being assigned to a program that was too far away. Finally, as for our fourth research question on whether the recidivism rate would differ between the two groups, we found that both groups had fewer total arrests after treatment assessment compared to before treatment assessment, however more untreated offenders were arrested in both time periods relative to treated offenders and improvements over time in arrests for drugs, “other,” and total offenses were smaller among untreated offenders. The study findings are congruent with our hypotheses that, compared to their treated counterparts, untreated Proposition 36 offenders would be more criminally severe and demonstrate a lower treatment motivation level however, contrary to our expectations, offenders in both groups demonstrated similar substance abuse problem severity at intake. Also, in keeping with our hypotheses, untreated offenders indicated that they chose Proposition 36 primarily to avoid incarceration and this was also the primary reason treated offenders gave for choosing the program. Surprisingly, the primary reason for treatment no-show was re-arrest and/or re-incarceration, not the belief that there was no substance abuse problem, however low motivation for treatment was the second most common reason for treatment no-show. Finally, findings were congruent with our expectation that untreated offenders would have a higher re-arrest rate than treated offenders.

The present study has several limitations. Our study captured a relatively small proportion of the larger statewide population of untreated Proposition 36 offenders and findings may vary with analysis of a wider spectrum of this group. The “untreated” grouping is self-reported at 3-months post-assessment and may have been affected by misrepresentation or recall errors. Also, treatment that may have been received immediately after the 3-month follow-up interview was not documented and so the potential influence of subsequent or additional treatment on recidivism could not be analyzed. However, at a 12 month follow-up interview offenders were asked whether they were currently receiving treatment, irregardless of the decision to initially enter treatment under Proposition 36 a year earlier, and significantly fewer individuals in the untreated group reported receiving care (21.4% vs. 41.8%), interestingly, primarily because of reenrollment in Proposition 36 (59.0%) (data not shown). As a final limitation, a relatively small sample of untreated offenders did not permit county-level analyses of topics for this paper, however prior work by the authors has documented distinctive Proposition 36 implementation policies and procedures as well as offender mixes by county (Hser, Teruya, Evans et al., 2003). County variation in Proposition 36 program practices and related outcomes poses important issues for future research.

It should also be noted that the difference in sample sizes between the untreated and treated groups posed some concerns for statistical testing. To verify our analyses, we conducted the nonparametric Wilcoxon-Mann-Whiteney test on all comparisons assessed by the t-test and we found few remarkable differences in results (see Table 2). Also, following Cohen (1977), we calculated the harmonic mean of the two sample sizes in our study as 227, indicating that there is enough power for the t-tests. For our categorical variables, the Pearson chi-square is a powerful test for detecting group differences and it is also fairly robust as long as no more than about 20% of expected cell counts are less than 5 (i.e., Agresti, 2002). However, unfortunately, no studies to our knowledge have addressed the issues associated with the GEE on repeated measure outcomes when the sample sizes of groups being compared are of very different sizes.

Despite these limitations, some useful findings have resulted from our unique study design. The study instruments are based on standardized instruments that have been widely used in previous studies among similar populations, self-report data are complemented by official records of arrests, and, as re-emphasized in recent literature on barriers to treatment entry (Rapp et al., 2006; Redko et al., 2006; Tsogia et al., 2001; Wild, 2006; Wild et al., 2006), offender attitudes and perceptions of the Proposition 36 program were documented.

Our findings pose several important implications for future Proposition 36 program planning and research. First, continued discussion is needed regarding the role treatment no shows play when measuring the effectiveness of the Proposition 36 program. On the one hand, most offenders who accept Proposition 36 do enter treatment, and of the smaller proportion of individuals who do not show up for treatment, some will enter care at a later date. In this sense, treatment no-shows may represent a valuable “escape valve” for individuals that are not ready to take advantage of treatment and who might be more successful in treatment at a later once motivation for treatment has increased. Furthermore, when examining the flow of offenders through the entire Proposition 36 “pipeline” (i.e., from determination of program eligibility, to assessment and referral to treatment, followed by treatment entry, and then by treatment completion) (Longshore et al., 2005), the issue of most concern is not the relatively smaller proportion of individuals who do not show up for treatment, but rather the much greater proportion (about 70%) of individuals who do enter treatment but drop out of it before treatment completion. Efforts geared toward improving the effectiveness of the Proposition 36 program might be best served by focusing on reducing early treatment drop out.

However, on the other hand, several of the barriers to treatment entry that were mentioned by offenders could be minimized by improvements to practice and policy, thereby perhaps increasing the odds that individuals who accepted Proposition 36 but are hesitant about actually entering care will enter treatment sooner. Strategies for managing the flow of Proposition 36 offenders from court into treatment have been identified previously (Longshore et al., 2004). Stakeholders should consider how to improve treatment entry rates by re-examining or developing protocols for handling re-arrests, low levels of offender motivation for treatment, and geographical obstacles to treatment entry. Additional considerations should include: the length of time between acceptance of the Proposition 36 program and treatment entry, strategies for engaging and retaining offenders who are waiting to enter treatment, offender perceptions of the assessment process itself, and the availability of needed care. Reasons for Proposition 36 treatment no-show are very similar to those provided by other treatment seeking populations, i.e., unstable treatment motivation, legal involvement, and conflicts related to transportation, program eligibility, and scheduling (Hser et al., 1998). Although the evidence is mixed (Garner, Godley, & Funk, 2002; Donovan et al., 2001; Lash et al., 2005), employing interventions to address barriers to treatment entry can prevent early attrition and may facilitate treatment entry (Gariti et al., 1995; Stasiewicz & Stalker, 1999). Ample research has indicated that treatment can work, but the benefits associated with treatment can be realized only if individuals actually enter care.

Second, our findings can contribute to discussions regarding potential changes to Proposition 36 eligibility criteria. Offenders who did not enter treatment were differentiated from offenders who did go on to enter treatment by a greater number of arrests and months of incarceration over the lifetime, a higher proportion of arrests for violent offenses in the 12 months prior to assessment for Proposition 36 treatment, and lower motivation levels for treatment. Motivation levels have been associated with treatment engagement and post-treatment outcomes (Longshore et al., 2004) and motivational enhancement has been identified as a key role drug treatment professionals can play when faced with unmotivated clients referred from the criminal justice system (Casselman, 2004). Expanding eligibility criteria to include examination of criminal justice history over the lifetime, in addition to recent events, and offering specialized care for unmotivated offenders may both be worthy of consideration.

Third, our findings provide some insight into offender reasons for accepting the Proposition 36 program. Very few offenders in both groups said they chose Proposition 36 to expunge his or her criminal record, contradicting beliefs that this benefit would serve as an incentive for program participation. Most offenders eligible for Proposition 36 have accrued a considerable criminal record and many may not view the erasure of one offense as a significant reward for program participation. Also, offenders likely understand that the small gain of record expungement will not be realized immediately, but rather it will occur over the long-term after completion of treatment and other Proposition 36 program requirements. The lack of short-term incentives combined with declining treatment motivation levels during the three months following assessment may negatively impact offender decision-making regarding continued program participation. The implementation of more immediate and meaningful rewards, and sanctions, could improve offender participation in the Proposition 36 program. Research is needed to identify effective rewards and sanctions and the inclusion of offender perspectives in such research would be valuable.

Fourth, our data confirm that Proposition 36 offenders are tough to treat. According to our results, untreated Proposition 36 offenders are not primarily low-level drug users who do not need drug treatment. Instead, untreated offenders are unmotivated for treatment despite substance abuse histories that are similar to treated groups, untreated offenders have extensive criminal histories, and untreated offenders commonly choose the Proposition 36 program to avoid immediate criminal justice sanctions. While analysis of a broader sample of untreated offenders may reveal sub-groups of low level drug users who have less substantial criminal histories, the type of untreated individual analyzed in this paper poses numerous challenges. Compared to a large study of the general treatment population in California that was implemented just prior to the initiation of Proposition 36 (Hser, Evans, Teruya et al., 2003), more Proposition 36 offenders have a severe criminal history (i.e., arrests and incarcerations) and almost twice as many recidivate in the year following treatment entry. This type of treatment client is not necessarily new to clinicians and treatment practitioners in California however Proposition 36 may have inadvertently introduced more of these challenging clients into the treatment system. To adequately handle this influx of hard-to-treat clients, incremental program improvements based on evidence-based promising practices (e.g., like those proposed by The Network for the Improvement of Addiction Treatment, www.niatx.net) should be considered.

Finally, more research is needed on how treatment populations have been changed by Proposition 36 and the impact of these changes on services and outcomes. Given that the literature has identified population-specific characteristics associated with treatment entry (Corsi et al., 2007; Jackson et al., 2003; Pelissier, 2004; Siegal et al., 2002), also needed is information on factors (e.g., offender variables, county context, and Proposition 36 program elements) that predict Proposition 36 treatment entry with particular emphasis on differences in predictors by gender, race/ethnicity, prior drug treatment, and criminal history. Additionally, although the effect of individual county-level policies for managing Proposition 36 offenders has been little studied, many of the barriers to treatment entry may be best curtailed with use of creative county-level strategies such as increased close coordination between treatment and criminal justice agencies in handling new arrests, routine use of motivational enhancement protocols at assessment, and expansion of transportation options. Finally, some untreated offenders will be offered the Proposition 36 program repeatedly and on these subsequent cycles many may actually enter treatment. This kind of treatment recycling gives Proposition 36 offenders another chance to receive needed care however to minimize the use of resources and associated expenses, strategies are needed to increase the odds that more individuals proceed from court to assessment to treatment entry on their first Proposition 36 experience. Moreover, more information about the prevalence, characteristics, and outcomes of Proposition 36 recyclers is needed to address whether barriers to treatment entry may be unique to this group of offenders. Lastly, the role of employment in Proposition 36 program participation, motivation level, utilization of services, and outcomes requires further study.

In conclusion, addressing offender substance abuse in addition to extensive criminal behavior and disinterest in treatment pose numerous challenges for Proposition 36 stakeholders and policymakers. As the Proposition 36 program evolves, additional information is needed to identify strategies for expanding program participation. Evidence-based research findings can inform improvements to public health practices regarding drug-abusing offenders by identifying ways to enhance perceptions of treatment, reduce barriers to treatment, and facilitate the efficient use of resources so as to maximize program benefits.