Abstract
Objectives. California’s Proposition 36 offers nonviolent drug offenders community-based treatment as an alternative to incarceration or probation without treatment. We examined how treatment capacity changed to accommodate Proposition 36 clients and whether displacement of other clients was an unintended consequence.
Methods. Treatment admissions were compared for the year before and 2 years after the law was enacted. Surveys of county administrators and treatment providers were conducted in Kern, Riverside, Sacramento, San Diego, and San Francisco counties.
Results. The number of Proposition 36 offenders admitted to treatment continued to increase in the state (approximately 32000 in Year 1 and 48000 in Year 2) and in the 5 counties; total treatment admissions stabilized in Year 2 after increasing in Year 1. Voluntary clients decreased by 8000 each year statewide, but the change varied across counties. One third of treatment providers reported decreased treatment availability for non–Proposition 36 clients in Year 2.
Conclusion. Despite expanded treatment capacity (mostly in outpatient treatment), indirect evidence suggests that displacement of voluntary clients may have occurred in part because of the demand for treatment by Proposition 36 clients.
California’s Proposition 36, enacted as the Substance Abuse and Crime Prevention Act of 2000, has been in operation for more than 5 years since its implementation in July 2001. This law allows (under certain conditions) adults convicted of nonviolent drug possession offenses to choose community-based drug treatment in lieu of incarceration or probation without treatment. Offenders on probation or parole who commit nonviolent drug possession offenses or who violate drug-related conditions of probation or parole can also receive treatment. The resulting increase in client flow has introduced considerable challenges for California’s publicly funded drug treatment system. The foremost concern expressed by those involved at all levels is how the treatment system is responding to accommodate the influx of Proposition 36 offenders.
We address the following questions: was the drug treatment system flooded with Proposition 36 clients (i.e., were more program slots necessary?), and did programs expand to meet the need? Were staff capacity and service capacity increased to meet the needs of Proposition 36 clients? Did Proposition 36 clients displace non–Proposition 36 clients, particularly those who were seeking treatment on their own?
The intent of Proposition 36 was to improve public health and safety via provision of substance abuse treatment. Its implementation highlights the critical interaction between the criminal justice and health service systems. Offenders often enter, are processed through, and exit the criminal justice system with health and health-related problems, including mental illness, disease (e.g., hepatitis C, tuberculosis, HIV), substance abuse, and homelessness.1–5 As such, the impact of the law on access to health services and drug treatment capacity for the criminal justice population has implications for other systems.
BACKGROUND AND CONCEPTUAL FRAMEWORK
Treatment capacity in the drug treatment system is often simply regarded as the number of available program slots (residential beds or outpatient slots). Our conceptualization of treatment capacity is multifaceted, however, involving program slots and characterized by facility and program capacity (i.e., physical structures and facility licensure and program certification), staff capacity (i.e., ratio of clients to staff, or caseload), service capacity (i.e., adequate and specialized services to meet clients’ needs), and funded capacity (i.e., funds to cover the costs of treatment). Increased numbers of clients will occupy more physical space in programs and require additional staff effort and time as well as services, all of which have associated costs. Thus, increased demands on the treatment system from Proposition 36 clients may affect (displace) non–Proposition 36 clients who would otherwise seek and receive treatment.
Under the law, Proposition 36 funds of $120 million per year (roughly one quarter of the statewide treatment funding available from all sources) could be used for capacity expansion: purchasing more treatment slots from treatment providers with existing county contracts, acquiring new (physical) facilities, and opening new programs (e.g., intensive treatment for women with children). However, only facilities and programs that have been licensed or certified by the state Department of Alcohol and Drug Programs are eligible to treat Proposition 36 clients. Furthermore, capacity expansion can be limited by licensing or certification requirements and funding. Therefore, to determine treatment capacity for Proposition 36 clients, one must consider availability of funded capacity in licensed facilities and certified programs, and, accordingly, whether treatment slots are sufficiently available at different levels of care or modalities that address clients’ varying and multiple needs. Studies have shown that clients treated in residential programs are typically more severely impaired than those treated in outpatient programs,6–8 and that methadone maintenance can successfully treat heroin users.9–11 However, residential programs are much more costly than outpatient programs,12–13 and are more difficult to expand, especially in the short time since the implementation of Proposition 36.
Proposition 36 funds can also be used for capacity expansion to hire additional treatment staff and to develop and provide new services. Comprehensive assessment of treatment capacity requires characterization of the extent of available services that meet the needs of clients beyond drug and alcohol services, such as psychiatric medications or transitional housing. Many clients have problems in multiple areas and, if left unsolved, these problems frequently interfere with clients’ participation in treatment or increase their risk for relapse. Moreover, Proposition 36 stipulates that funds may also be used to provide vocational training, family counseling, and literacy training in addition to substance abuse treatment. Thus, it is important to examine whether programs serving Proposition 36 clients are actually providing these services.
A related issue is that if priority is given to Proposition 36 clients over non–Proposition 36 clients when treatment capacity cannot accommodate the needs of both groups, displacement can occur. Displacement may be indicated by a reduction in the number of voluntary or otherwise referred clients, fewer treatment slots or services available, longer wait times, shortened treatment duration, and greater client-to-counselor ratios for non–Proposition 36 clients.
On the basis of this conceptual framework, we explored the impact of Proposition 36 on treatment capacity in California. We analyzed the statewide database of client treatment admission and discharge records to assess changes in client populations in California overall and in 5 selected counties (Kern, Riverside, Sacramento, San Diego, and San Francisco). We also examined the perspectives of county administrators and treatment providers involved in Proposition 36 implementation and service delivery in these counties. In the discussion, we reflect upon the public health implications of the findings.
METHODS
Client Data
Client characteristics were derived on the basis of data collected in the California Alcohol and Drug Data System, which contains admission and discharge records of all clients admitted to publicly funded alcohol and drug programs or to private state-licensed methadone programs.
Treatment Program Survey
All programs serving Proposition 36 clients in the 5 study counties were invited to participate in a survey to assess the impact of the law on local treatment service delivery systems during the first 2 years of the law. Program personnel (e.g., directors, managers, supervisors, coordinators) from 126 of 137 programs (92%) completed the self-administered questionnaire. These 126 programs, comprising 141 service delivery units, included outpatient drug-free (ODF; n = 79), residential (n = 37), mixed modality (n=5), and methadone (n=5) programs. The survey took approximately 1 hour to complete, and respondents were offered $100 for their participation.
County-Level Data
Perspectives on treatment capacity in the 5 study counties were also collected from 42 county-level personnel (e.g., administrators of the lead agency responsible for local implementation and compliance with state regulations [e.g., Alcohol and Drug Services, Department of Public Health] and those responsible for substance abuse treatment and mental health services, as well as judges, district attorneys, public defenders, and probation or parole officials) via a self-administered questionnaire and face-to-face semistructured interviews (92% completion rate). The questionnaire took about 2 hours to complete and the interview lasted approximately 2 hours. Respondents were paid $100 for their participation if payment was not in violation of agency or county policies.
RESULTS
Facility and Program Capacity
Compared with the year before Proposition 36 implementation, total statewide treatment admissions during the first year after Proposition 36 implementation increased 11%; in 4 of the 5 selected counties (except San Francisco), increases ranged from 11% to 34% (Table 1 ▶). Increases were mostly in admissions to ODF programs (from 37% in San Diego to 60% in Sacramento, and 34% statewide). (Modality-specific data for the state are shown in Figure 1 ▶.) On the other hand, there were decreases in admissions to methadone programs across counties as well as statewide (20%). In the second year, total general treatment admissions in these counties remained fairly stable (from an increase of 8% in Riverside to a decrease of 10% in San Francisco), as it did statewide (1% increase), and there were continued decreases in admissions to methadone programs (16% statewide).
TABLE 1—
Sources of Referral for Drug Treatment 1 Year Before and in the First 2 Years After Proposition 36 in 5 California Counties and California State
| Kerna,b | Riversidea,b | Sacramentoa,b | San Diegoa,b | San Franciscoa,b | Statea,b | |
| Pre-P36 | 4614 | 7472 | 5119 | 19 379 | 19 383 | 219 522 |
| Self | 1485 | 3034 | 2371 | 8285 | 7075 | 103 447 |
| P36 | 0 | 0 | 0 | 0 | 0 | 0 |
| Non-P36 CJSc | 2293 | 1935 | 933 | 8027 | 3230 | 61 021 |
| Othersd | 836 | 2503 | 1815 | 3067 | 9078 | 55 054 |
| Year 1 | 6178 | 9055 | 6557 | 21 669 | 16 028 | 243 242 |
| Self | 1284 | 2864 | 2269 | 7694 | 4623 | 95 462 |
| P36 | 1696 | 1460 | 1605 | 3510 | 178 | 32 199 |
| Non-P36 CJSc | 2353 | 2336 | 666 | 8368 | 3264 | 60 562 |
| Othersd | 845 | 2395 | 2017 | 2097 | 7963 | 55 019 |
| Year 2 | 5841 | 9790 | 6912 | 20 175 | 14 475 | 245 078 |
| Self | 1063 | 2578 | 2288 | 6644 | 4038 | 87 968 |
| P36 | 2431 | 2241 | 1782 | 3577 | 327 | 48 032 |
| Non-P36 CJSc | 1665 | 2110 | 606 | 8113 | 3159 | 56 421 |
| Othersd | 682 | 2861 | 2236 | 1841 | 6951 | 52 657 |
Notes. P36 = Proposition 36; CJS = criminal justice system.
aBased on the California Alcohol and Drug Data System (October 2004) for the respective county or the state.
bStatistical tests on changes in self-referred admissions over time were conducted for the 5 counties and for the state. For counties, analysis of covariance was conducted to test effects of county, time, and the interaction of the 2 on self-referrals.
Results showed significant time effect (F1,5 = 37.1; P < .01) and county effects (relative to San Francisco, all with P < .01). For the individual county, a linear function of the parameter in the model was tested using the F statistic. For the state, a simple
regression model was tested and the result showed significant time effect (F1,1 = 2981; P < .01).
cIncludes referral by any police official, judge, prosecutor, probation or parole officer, or other person affiliated with a federal, state, or county judicial system other than referrals funded by Proposition 36.
dIncludes alcohol and drug programs, other health care providers, schools, employers, 12-step mutual aid, and other community referral.
FIGURE 1—

Trend analysis of treatment admissions in residential programs (a), outpatient drug-free programs (b), methadone programs (c), and overall (d).
Note. Proposition 36 (vertical bar) took effect on July 1, 2001.
Trend analysis (description of the analytic method and results can be provided upon request) showed that statewide, only admissions to ODF significantly increased in both Year 1 and Year 2 beyond the expected historical fluctuation. Riverside and San Diego counties demonstrated significant increases in ODF admissions, whereas San Diego and San Francisco counties showed significant decreases in admissions to methadone programs after Proposition 36 was implemented.
As shown in Table 1 ▶, Proposition 36 admissions increased from the first to the second year in all 5 counties (P< .05), similar to the statewide trend (approximately 32 000 in Year 1 and 48 000 in Year 2, a 50% increase; Figure 1 ▶). There were wide county variations in percentages of increase from the first year, with 84% in San Francisco (because of the small number of Proposition 36 clients in Year 1), 53% in Riverside, 43% in Kern, 11% in Sacramento, and 2% in San Diego. Increases in residential clients ranged from 168% in Kern (because of the small number in the first year), 47% in Riverside, 24% in San Diego, to 15% in Sacramento. Increases in Proposition 36 clients entering ODF programs (55% in Riverside, 41% in Kern, 12% in Sacramento) were observed in all counties except San Diego (4% decrease). Few Proposition 36 clients were treated in methadone programs (only 403 admissions in Year 1 and 661 in Year 2, statewide).
Some counties (i.e., Sacramento and San Francisco) worked with a limited number of designated treatment programs to provide services for their Proposition 36 clients, whereas others (i.e., Kern, Riverside, and San Diego) had a more distributed system that included most or all of their existing contracted programs. To place and serve the large number of Proposition 36 clients, outpatient programs experienced the most expansion in (funded) capacity. Most counties worked with existing facilities that already held county contracts before Proposition 36 took effect, and a few counties (e.g., Riverside) expanded their capacity by contracting with formerly nonaffiliated facilities. Of the 126 facilities surveyed, 22 (17.5%) started serving Proposition 36 clients in Year 2, suggesting a 21% increase in treatment programs that served Proposition 36 clients in these 5 counties. Some counties (i.e., Kern and San Diego) did not fund or contract with methadone (detoxification or maintenance) programs for Proposition 36 clients. Among the selected counties, Sacramento had the highest proportion (45%) of heroin-abusing offender admissions being treated in methadone programs.
The waiting time for Proposition 36 clients to be placed in programs after assessment was typically less than a week for all counties, perhaps because of the wide use of ODF program placement. Nonetheless, administrators in all counties (except Kern) cited residential treatment as 1 of their county’s top-3 urgent needs, particularly for offenders with co-occurring mental disorders. Less than 20% of all program survey respondents indicated insufficient treatment capacity for Proposition 36 clients in Year 1, and 25% to 40% did so for Year 2 (although the difference between years was not significant).
Staff Capacity
In the 5 selected counties, the mean number of staff (counselor and other positions) per program hired for or reassigned to Proposition 36 clients was 2.1 (standard deviation [SD]=3.3) in Year 1 and 2.2 (SD=3.4) in Year 2, and the mean number of staff that left during the same period was 1.1 both in Year 1 (SD=2.8) and in Year 2 (SD=3.0). The net increase in counselors was significantly higher for ODF programs than for residential programs in Year 1 (P<.05). For individual counties, significant net increases in ODF program counselors were observed in Kern (Year 1), Sacramento (Year 2), and San Diego (both years). Net increases in staff in other positions were also observed in all counties (except for Kern), and were mostly for ODF programs in Year 1.
The caseload pattern (number of Proposition 36 clients per counselor) did not change over time but varied considerably across counties. Programs in Kern reported the highest counselor caseload: the mean caseload was 12 in residential programs and 26 in ODF programs in the first year and increased to 20 in residential programs and 28 in ODF programs in the second year. Slight changes were observed in Riverside, San Diego, and San Francisco, with no change in Sacramento (an average of 6 clients per counselor in residential programs, and 31 clients per counselor in ODF programs). None of these changes was significant.
Service Capacity
All counties provided assessment, placement, and referral services for Proposition 36 clients. Eighty percent of the counties reported developing new strategies for dealing with co-occurring substance abuse and mental health disorders. Sixty percent reported provision of sober living environments and 40% offered transitional housing for Proposition 36 clients.
At the program level, few changes can be discerned from the survey, as services for Proposition 36 offenders did not appear to have changed much from either those available for non–Proposition 36 clients or those offered before the new law. Planned treatment durations for Proposition 36 clients ranged from 3 to 6 months for outpatient and less than 3 months for residential programs (except for San Diego). Most facilities provided referrals for aftercare.
Across the 5 counties, between 50% and 100% of treatment programs reported providing family counseling, 20% to 80% provided vocational training, and less than 50% provided literacy training; increases in the number of programs providing these services over time were small and occurred only in a few counties, and then only in the first year of the law.
Displacement of Non–Proposition 36 Clients
The number of Proposition 36 clients continued to increase over the first 2 years but general treatment admissions to publicly funded programs became stable after the initial increase. To determine whether treatment availability for non–Proposition 36 clients was reduced, we further examined the treatment client database to investigate patterns of referral sources. As shown in Table 1 ▶, reductions in self-referrals (voluntary clients) were observed consistently over the 3 years, across the counties (significant in San Diego, [F1,5 = 10.8; P = .02] and San Francisco [F1,5 = 37.1; P = .002]) as well as the state (a reduction of approximately 8000 admissions per year [F1,1 = 2981; P = .01]), and to a lesser extent, among non–Proposition 36 criminal justice referrals (e.g., drug court, probation; for the state, F1,1 = 4.7; P = .28).
About 33% of treatment providers reported decreased treatment capacity for non–Proposition 36 clients in terms of fewer treatment slots, less provision of treatment services, and increased ratios of non–Proposition 36 clients to counselors.
DISCUSSION
Proposition 36 introduced an unprecedented number of clients into California’s drug treatment system. Overall treatment admissions increased by 11% to 34% during the first year in 4 of the 5 counties studied, with an 11% increase statewide. No parallel increases have been observed in drug use prevalence14 or in drug law enforcement15 during these periods. In the law’s second year, few changes in overall admissions were observed in the 5 counties and the state, but the number of Proposition 36 offenders entering drug treatment continued to increase in all counties and statewide (50% increase over Year 1). Except for San Francisco county, Proposition 36 clients in Year 2 constituted 18% to 42% of the total admissions in the studied counties’ treatment systems and 20% of the state’s treatment system, which is a significant proportion given the brief time since implementation. This expansion has occurred mainly in ODF programs, with concurrent reductions in self-referrals and admissions to methadone programs. These findings suggest that treatment capacity and availability for non–Proposition 36 clients might be compromised in the majority of California counties.
Facility and Program Capacity
Most counties contracted with existing licensed or certified providers and allocated the vast majority of Proposition 36 funds to ODF treatment as a cost-efficient means to accommodate the large flow of Proposition 36 offenders. However, ODF treatment may not be optimal for certain subpopulations of Proposition 36 clients, such as those who are homeless or who have co-occurring substance abuse and mental health disorders.
Proposition 36 admissions to methadone detoxification or maintenance were extremely low in most counties (except Sacramento), similar to levels in the state (about 1% of all admissions), although heroin abusers accounted for 11% to 12% of the state’s Proposition 36 offenders. These low rates are likely because of the criminal justice system’s longstanding rejection of methadone as a viable treatment option for its clients. Regardless of the reason for the low rates, brief ODF treatment may not be sufficient for heroin addicts as they typically have more severe problems.6,16 We have observed disproportionately higher rates of heroin-abusing Proposition 36 admissions treated in residential programs (close to 30%, in contrast with 15% of Proposition 36 offenders whose primary drug was not heroin). It is, however, unclear why there has been an overall decline in heroin admissions in California’s treatment system (about 11% reduction each year statewide); this phenomenon should be examined in future studies.
Staff Capacity
Modest increases were observed in staffing in individual treatment facilities, which may appear to be at odds with the large increases in treatment admissions. However, as mentioned earlier, some counties handled the increased admissions by expanding their contracts with existing and new facilities (in counties such as Riverside) over time; our survey has revealed a 21% increase in the number of facilities in Year 2 relative to Year 1. Thus, even if staff capacity within programs did not change, the total capacity in the county increased because of the additional facilities serving Proposition 36 clients. It is also possible that because most of the increase has taken place in ODF programs, and ODF programs typically provide their services in group settings, programs may have placed more clients in existing treatment groups without hiring additional staff.
Service Capacity
Some new services were reported by lead agencies in most of the studied counties. In particular, new strategies for dealing with co-occurring disorder clients were mentioned in 4 of the 5 counties.17 However, treatment providers reported few changes in services, although they reported some increases in the provision of vocational and literacy training. It is possible that these treatment programs were already offering a variety of services, as almost half of the treatment population in California were criminal justice referrals with multiple problems before Proposition 36,18 similar to the rest of the country.7 Assessment of which and how many services were actually received by clients is needed to ascertain the actual changes in service capacity.
Displacement
Displacement of non–Proposition 36 clients may have occurred in California’s treatment system (except for a few counties such as San Francisco, where Proposition 36 cases have been relatively few), as suggested by the findings and several observations from our study. First, few new facilities were established to serve Proposition 36 clients; Proposition 36 clients were mostly treated in existing facilities. Although there was some increase in treatment staff, these increases were modest, particularly with the consideration that many staff left the programs during the same periods.
Second, general treatment admissions leveled off in Year 2, while Proposition 36 clients continued to increase. Reductions were found in self-referrals and non–Proposition 36 criminal justice system referrals with concurrent increases in Proposition 36 clients; these reductions imply reduced access to public treatment because the California Alcohol and Drug Data System included all admissions to facilities receiving any public funding. Although it is possible that some formerly voluntary clients later became Proposition 36 clients, the extent must be limited because there was no evidence of any systematic change in arrest or charging practices.15
Third, Proposition 36 clients were significantly different in terms of demographics and other characteristics (i.e., most were male methamphetamine and amphetamine abusers being admitted to their first treatment experience) from non–Proposition 36 clients or clients in years before Proposition 36,17 potentially indicating a new type of client entering the treatment system.
Proposition 36’s impacts on non–Proposition 36 clients could pose considerable problems if Proposition 36 clients continue to increase without additional capacity expansion in facilities, staffing, and services. The current budget crisis in the state could further compromise service availability for both Proposition 36 and non–Proposition 36 clients.
Conclusions
Proposition 36 has successfully brought a large number of drug-abusing offenders to treatment in a very short time period, many for the first time.15,17 Although this is an important first step, positive therapeutic effects require clients’ engagement in appropriate treatment over a sufficient period of time,8 and positive outcomes depend on services that effectively address clients’ multiple needs.19–22 Treatment capacity expansion for Proposition 36 offenders was observed mostly in ODF programs, often with short planned durations, which may not be adequate for severe-level drug abusers, for heroin addicts, and particularly for clients with co-occurring mental disorders and other intensity and duration) has been found to be associated with high rates of recidivism.23
Although more direct evidence for displacement (e.g., longer wait time for non–Proposition 36 clients) should be sought, our findings suggest that displacement may be an unintended negative consequence of Proposition 36 that needs further investigation. Is the perceived or actual unavailability of treatment or inadequate level of available treatment for voluntary clients contributing to a lower rate of help seeking and, thus, to the ongoing public health and safety problems of untreated addiction? There has been some indication that policies promoting “treatment on demand” have increased access only for some populations, but not for the indigent or for opiate addicts needing methadone maintenance.24 It has also been suggested that increased case-loads result in increased pressures on programs and staff, which undermine treatment objectives.25 The ways in which diverted offenders impact the substance abuse treatment system require further investigation, and the implications for other health service systems need to be more thoroughly considered.
Because resources are limited in California, it could be argued that displacement of voluntary clients by those who are criminally involved, such as Proposition 36 clients, may produce greater benefit to society (e.g., reduced drug use and associated criminal activities). To temper this assertion, however, previous research has shown that drug addiction tends to develop into a chronic condition that often includes criminal activity.6,16 By delaying or denying their treatment, drug abusers without criminal histories may later become criminally involved addicts. Policymakers and the public need to carefully consider the long-term implications of a policy that directs resources at one critical population while potentially diverting resources from another.
Acknowledgments
The study was supported in part by the National Institute on Drug Abuse (grant R01DA15431). Yih-Ing Hser and M. Douglas Anglin are also supported by National Institute on Drug Abuse Independent Scientist Awards (K02DA00139 and K05DA00146, respectively).
The authors wish to thank the administrators from the 5 participating counties (Kern: Lily Alvarez, Allen Belluomini, Etta Robin; Riverside: Frank Lewis, Al Bell, Maria Lozano; Sacramento: Toni Moore, Sharon DiPirro-Beard, Jessica Vierra; San Diego: Al Medina, Linda Bridgeman-Smith, Susan Bower; San Francisco: Tom Hagan, Michael Ford, Craig Murdock) for supplying information and supporting the study. We also express our appreciation to the staff at the University of California, Los Angeles, Integrated Substance Abuse Programs for their assistance in the preparation of the article.
Note. The content of this publication does not necessarily reflect the views or policies of the National Institute on Drug Abuse.
Human Participant Protection This study was approved by both the University of California, Los Angeles, and the California State institutional review boards. Participants provided informed consent.
Peer Reviewed
Contributors All authors contributed to the conceptualization of ideas and interpretation of findings, and reviewed the article. Y.-I. Hser originated the study and led the writing. C. Teruya contributed to the writing and overall development of the article. A. H. Brown helped develop the literature review and conceptual framework. D. Huang conducted the statistical analyses.
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