Alcohol Use and Moffitt's Maturity Gap Thesis for Adolescent Offending: An Evolutionary Perspective and Analysis

Abstract

While a wealth of research has focused on testing several arguments from Moffitt's developmental taxonomy of antisocial behavior—mainly the presence of life-course-persistent vs. adolescence-limited offending and predictors of each trajectory—much less attention has been devoted to examining how evolutionarily adaptive lifestyle factors common during adolescence may condition the relationship between the maturity gap and delinquent offending. One factor that may play a role during this period of development is alcohol use, as many adolescents begin to experiment with consuming alcohol in varying degrees in social settings to model adult-like behaviors. Yet presently much is unknown about the role of alcohol use on the association between the maturity gap and delinquency. The current study aims to address this void in the literature by analyzing data from a U.S. sample of adolescent males (N = 1,276) to assess whether alcohol use moderates the relationship between the maturity gap and delinquent behavior. Findings suggest that the maturity gap is associated with delinquent behavior and that the association becomes weaker at higher levels of alcohol use. The implications of these findings for Moffitt's maturity gap thesis and male offending from an evolutionary perspective are discussed.

Introduction

To better explain the age-crime curve and the observation that a small percentage of offenders account for a large proportion of crime, Moffitt (1993) proposed a developmental taxonomy theory of antisocial behavior. Through analyzing life-course data from childhood to adulthood, Moffitt (1993) defined life-course-persistent (LCP) offenders as a small group of individuals who engage in serious forms of antisocial behavior and do not desist from this behavior throughout multiple stages of their life. Adolescence-limited (AL) offenders are defined as the largest proportion of offenders who engage in antisocial behavior during adolescence and then desist in adulthood. Lastly, abstainers are suggested to be those who do not engage in any form of antisocial behavior across the life-course.

One of the primary explanations for AL offending during adolescence suggested by Moffitt (1993) is the maturity gap. The maturity gap argues that biological and social maturity are distinct constructs, and those who are caught in a gap between their biological and social maturity will be more likely to engage in antisocial behaviors. Specifically, those with advanced biological maturity, but relatively less social autonomy, are more likely to commit delinquent acts to cope with frustrations and in an attempt to appear more mature. Moffitt (1993) proposes that adolescents who are frustrated with this gap mimic behaviors of LCP peers, who engage in delinquency as a means of increasing their social autonomy.

During adolescence, many begin to experiment with alcohol use (Spear, 2002). It has been suggested that those who display higher impulsivity are more likely to develop antisocial behavior and problematic alcohol use behaviors (Defoe et al., 2022). Moeller and Dougherty (2001) report that those with antisocial personality disorder are more likely to display aggressive behaviors when intoxicated by alcohol. Alcohol use is an important evolutionary factor to consider when evaluating increases in delinquent behavior during adolescence because it may help to increase fitness by signaling to potential mates that the consumer is able to find food sources or make use of excessive calories from alcohol while avoiding consequences from toxicity (Clites et al., 2023). While previous tests of Moffitt's maturity gap hypothesis have found support for its explanatory power for illicit drug use behaviors (Barnes & Beaver, 2010), few studies have investigated the interactive effects of alcohol use on the link between the maturity gap and delinquency in general. Given the associations between both the maturity gap and alcohol use with delinquent and antisocial behaviors, one may expect interactions between these factors that give rise to delinquency. The current study aims to fill this gap in the literature by assessing the direct and moderating effect of alcohol use on the association between the maturity gap and delinquency in a sample of adolescent males from the United States.

The Maturity Gap Thesis

Moffitt's (1993) maturity gap thesis has been suggested as a potential explanation for the age-crime curve observed in AL offenders. Specifically, Moffitt (1993) suggests that ALs engage in delinquent behaviors to alleviate frustrations with reduced social autonomy relative to their biological maturity. ALs who have reached reproductive maturity, yet are denied the social freedoms of adulthood, mimic the behavior often demonstrated by their LCP peers who seem to better cope with this gap through delinquent behaviors (Moffitt, 1993). In line with this thesis, Barnes et al. (2011) found in a sample of 6,503 adolescents that those who do not experience discrepancies between their biological and social maturity are less likely to engage in delinquency over time, compared to their peers. Findings from this study further suggest that those who have less peers who use substances are more likely to abstain from delinquent behavior (Barnes et al., 2011).

Subsequent tests of Moffitt's (1993) maturity gap hypothesis have generally found support for this as an explanation of less serious forms of antisocial and delinquent behaviors (Barnes & Beaver, 2010; Craig et al., 2017). For example, Ozkan and Worrall (2017) reported that psychosocial maturity did not interact with either pubertal maturity or social maturity, but it was directly related to delinquent behavior. In a sample of 970 Dutch adolescents, Hill et al. (2016) also found that taking on adult roles aided in desistance from delinquency. In perhaps the most direct test of Moffitt's maturity gap thesis, Barnes and Beaver (2010) used data from a large sample of U.S. adolescent males and found that the maturity gap predicted minor delinquency (i.e., painting graffiti, lying to parents, and running away from home) and drug use, but not serious types of offending behavior (i.e., aggression, stealing a car, and selling drugs).

The Role of Alcohol Use for the Maturity Gap and Adolescent Delinquency

Adolescent substance use has been a growing public health concern in the United States (Garofoli, 2020). Initiation of alcohol use has been identified as a risk factor for negative life outcomes, such as poor health and greater frequency of substance use behaviors (DeWit et al., 2000; Donovan, 2004; Smit et al., 2018). Moreover, adolescent alcohol use has been associated with greater involvement in delinquent and criminal offending (Dijkstra et al., 2015; Masson & Windle, 2002). Previous research has identified alcohol use as a contributing factor in a large proportion of criminal behaviors (Denson et al., 2018). Denson et al. (2018) assert that it is one of the strongest psychotropic predictors of violence and aggression. Furthermore, alcohol use has been associated with offending in both LCP and AL offenders (Moffitt, 1993) as well as antisocial behaviors in adulthood (Howard et al., 2012; Khalifa et al., 2012). For example, in a sample of 477 young adults, Howard et al. (2012) reported that early onset alcohol use moderated and partially mediated the relationship between childhood conduct disorder and adult antisocial behavior. These findings were confirmed in a forensic British sample of one hundred males (Khalifa et al., 2012). Similarly, Dijkstra et al. (2015) showed that parental conflict (produced through the maturity gap) was associated with greater amounts of delinquent behavior and substance use over time. Indeed, it has been hypothesized that engagement in alcohol use creates a sense of independence (Moffitt, 1993), or an avenue for expressing frustrations with issues resulting from the social and biological maturity misalignment (Agnew, 2003; Dijkstra et al., 2015). Thus, while alcohol use is a common correlate of antisocial behavior, it may weaken the connection between stress felt as a result of the maturity gap and subsequent delinquent behavior in adolescence.

From an evolutionary perspective, while the negative consequences of prolonged alcohol use are plentiful, adolescent alcohol use may serve a purpose in improving environmental fitness. Indeed, alcohol use (from fermented fruits) among shared ancestors between early humans and primates may have been selected for as this quality could indicate one's ability to find food sources, or an ability to use excess calories (Clites et al., 2023). Further, it has been suggested that those who display higher levels of impulsivity and antisocial behaviors may use alcohol as a means of increasing peer relations (Gerald & Higley, 2002). For those caught in a maturity gap, engaging in alcohol use may aid adolescents in developing social interactions that enable them to close the gap between their social and biological autonomy by modeling adult drinking behavior.

The Current Study

The current study aims to build off previous tests of Moffitt's (1993) maturity gap thesis by assessing the moderating role of alcohol use on the relationship between the maturity gap and delinquency. Using measures of biological maturity and social autonomy from a large, population-based sample of male youth, we assess the relationship between a constructed measure of the maturity gap and alcohol use with delinquent behavior. We test several hypotheses. First, we predict that those caught in the maturity gap (i.e., those with advanced biological maturity relative to their social maturity) will be more likely to report engaging in delinquency, than those not caught in the gap. Second, we predict that those who use alcohol more frequently will be more likely to report engaging in delinquent behavior. Finally, based on evolutionary theory, we predict that the relationship between the maturity gap and delinquency will be weakened as a result of more alcohol use; however, the degree of moderation is unknown and cannot be hypothesized based on the lack of existing empirical research and sound theory.

Methods

Data

Data for the current study are drawn from the National Longitudinal Survey of Youth 1997 (NLSY97). The NLSY97 is a population-based, longitudinal assessment of youth between the ages of 12 and 16 in 1997. This is a large and diverse sample, collected by the Bureau of Labor Statistics, to provide information regarding educational experiences and family background factors that may influence labor market behaviors. The NLSY97 dataset consists of 19 rounds of data collection between the years of 1997 to 2020. Data were collected annually from 1997 (Wave 1) to 2011 (Wave 14) and biennially from 2012 (Wave 15) to 2020 (Wave 19). Data consist of self-report and parent measures from 8,984 participants. Hispanic and non-Hispanic Black participants were oversampled from 75,291 households across 147 non-overlapping metropolitan areas or counties. The current study uses a subsample of males who were asked to respond to questions about the onset of their pubertal changes during the 1997 data collection period (Wave 1) and who had valid scores on both self-report and parent-report questions used to measure social maturity. As a result, the final analytic sample for the study included N = 1,276.

Measures

Maturity Gap. The maturity gap was measured by two measures for males that captured biological maturity and social maturity via parental control/autonomy limit setting during the 1997 wave of data collection. Biological maturity was assessed by asking if signs of puberty had begun, started, were underway, or appeared completed. These signs included physical changes, such as developing pubic or facial hair, or voice cracking or lowering. Response categories were: 1 = have not yet begun, 2 = have barely started, 3 = are definitely underway, and 4 = seem completed.

Social maturity was measured by participant and parent reports of the degree to which youth are granted autonomy and parents have a role in setting limits with regard to friends, curfew, and TV watching (Eccles et al., 1991; Erford, 1995). Youth and a parent were asked the following questions: (1) who sets the limits on how late you stay out at night?; (2) who sets the limits on who you can hang out with?, and; (3) who sets the limits on what kinds of TV shows or movies you can watch? Items were measured the same for youth and parents where: 1 = parents set limits, 2 = parents let me decide, and 3 = my parents and I decide jointly. Items were recoded such that 0 = parents set limits, 1 = youth and parents set limits, and 2 = youth set limits. All values were summed together to create an index of control/autonomy limit setting (range: 0–6). Youth and parent assessments were moderately correlated (r = .30). Scores were then added together and standardized to create a measure of control/autonomy limit setting.

The direct measure of the maturity gap was created by subtracting the values for biological maturity (where higher values represent more maturity) from values for the social maturity index (where higher values also reflect more autonomy). Values of zero on the maturity gap measure indicated that the respondent's biological maturity and their social maturity were equal. Values less than zero indicated that their biological maturity was less than their social maturity—suggesting that they were not caught in the maturity gap. Values greater than zero on the maturity gap variables indicated that the respondent's biological maturity was greater than their social maturity—indicating that they were caught in the maturity gap. Table 1 presents descriptive statistics for these measures.

Table 1.

Descriptive Statistics.

	Mean/%	SD/n	Min	Max
Delinquency	1.10	1.40	0	7
Biological maturity
Puberty change underway	2.67	.78	1	4
Social maturity
Youth reported autonomy	3.43	1.53	0	6
Parent reported autonomy	4.32	1.27	0	6
Maturity gap	−2.92	2.09	−8	3
Age puberty began	11.53	1.21	5	14
Alcohol use	.32	1.83	0	25
Alcohol using peers	1.35	.78	1	5
Family income	$48,626	$23,641	0	$250,000
ASVAB	45.58	30.10	1	99
Age	12.78	.68	12	14
12 years old	36.68%	468	-	-
13 years old	48.12%	614	-	-
14 years old	15.20%	194	-	-
Race
Black	22.57%	288	-	-
Hispanic	18.10%	231	-	-
Mixed Race (Non-Hispanic)	.63%	8	-	-
Non-Black/Non-Hispanic	58.70%	749	-	-

Alcohol Use. Adolescent alcohol use was measured during the 1997 assessment period (Wave 1) of the NLSY97 by asking participants to report how many times in the past 30 days they had drunk one or more drinks of an alcohol beverage. Responses ranged from 0 to 30.

Delinquency. Delinquent offending was measured during 1997 (Wave 1) by asking participants to report if they had ever engaged in the following behaviors: (1) carried a handgun; (2) purposely damaged or destroyed property that did not belong to you; (3) stolen something from a store or something that did not belong to you worth less than 50 dollars; (4) stolen something from a store, person or house, or something that did not belong to you worth 50 dollars or more including stealing a car; (5) committed other property crimes such as fencing, receiving, possessing or selling stolen property, or cheated someone by selling them something that was worthless or worth less than what you said it was; (6) attacked someone with the idea of seriously hurting them or have had a situation end up in a serious fight or assault of some kind, and; (7) sold or helped to sell marijuana (pot, grass), hashish (hash), or other hard drugs such as heroin, cocaine, or LSD. Responses to each item were binary (0 = no, 1 = yes). Responses were summed together to create a variety index of delinquency. The index demonstrated adequate internal reliability (Kuder–Richardson coefficient = .66).

Control Variables. Control variables include verbal intelligence measured by ASVAB percentile scores, age of puberty captured by a self-report question asking participants how far along in puberty (e.g., physical changes, such as developing pubic or facial hair, or the voice cracking or lowering) they believe they are (1 = have not yet begun, 2 = have barely begun, 3 = are definitely underway, and 4 = seem completed), alcohol using peers captured by asking participants to report the percentage of peers who get drunk at least once a month (1 = almost none [less than 10%], 2 = about 25%, 3 = about half [50%], 4 = about 75%, and 5 = almost all [more than 90%]), family income measured by reported net family income during the first two waves of data collection (i.e., 1997 and 1998), age measured in years at the 1997 survey wave, and race was self-reported and coded as: 1 = Black, 2 = Hispanic, 3 = Mixed Race (Non-Hispanic), and 4 = Non-Black/Non-Hispanic.

Plan of Analysis

The analysis was carried out in a series of sequential steps. First, bivariate correlations were assessed to determine the strength and direction of association between key variables of interest. Specifically, the strength and significance of the relationship between the maturity gap, alcohol use, and delinquency, as well as all other theoretically relevant controls. Second, a series of negative binomial regressions were used to assess the unique and interactional relations between the maturity gap, alcohol use, and delinquency. An initial multivariate model was estimated to assess whether the maturity gap and alcohol use were independently associated with delinquency. A second model was then estimated with an interaction term between the created measure of the maturity gap and alcohol use to test whether the strength of the association varied across values of alcohol use frequency. All analyses were conducted using Stata 15.1 (StataCorp, 2017) and regression models were calculated with robust standard errors.

Results

Table 2 shows the bivariate Pearson correlation coefficients for all measures included in the analysis. Delinquency was significantly and positively associated with biological maturity (r = .12; p < .001), the maturity gap (r = .18; p < .001) and alcohol use (r = .32; p < .001), and was significantly and negatively associated with social maturity (r = −.16; p < .001). Therefore, male participants who reported drinking alcohol on more days, were more biologically mature and less socially autonomous, reported more delinquency. Alcohol use was also significantly and negatively correlated with social maturity (r = −.12; p < .001) and positively associated with the maturity gap (r = .13; p < .001), suggesting that those who were less socially independent and caught in the maturity gap reported consuming more alcohol.

Table 2.

Bivariate Correlations.

	1.	2.	3.	4.	5.	6.	7.	8.	9.	10.
1. Delinquency	-
2. Biological maturity	.12**	-
3. Social maturity	−.16**	−.17**	-
4. Maturity gap	.18**	.52**	−.73**	-
5. Age puberty began	−.05	−.19**	.03	−.09**	-
6. Alcohol use	.32**	.06	−.12**	.13**	.01	-
7. Alcohol using peers	.19**	.20**	.15**	.18**	.27**	.20**	-
8. ASVAB	−.10**	.06	−.18**	.18**	.05	−.03	−.14**	-
9. Family income	−.11**	−.08*	.12**	−.11**	−.07*	.04	.13**	.18**	-
10. Race	.01	.02	−.10**	.10**	.05	.02	−.06	.45**	.15**	-

Notes: ** p < .001; * p < .01.

Table 3 presents the results from the negative binomial regression models predicting delinquency. As can be seen in Model 1, the maturity gap was significantly and positively associated with self-reported levels of delinquency (IRR = 1.10; 95% CI = 1.06–1.14), suggesting that male participants who were caught in the maturity gap reported more acts of delinquency. Males who reported drinking alcohol more frequently (IRR = 1.07; 95% CI = 1.04–1.11), having a higher percentage of friends who drank alcohol (IRR = 1.20; 95% CI = 1.11–1.30), and lower ASVAB scores (IRR = .99; 95% CI = .98–.99) also reported more acts of delinquent behavior. The age at which males started noticing biological changes reflecting the onset of puberty was not, however, associated with delinquent offending (IRR = .96; 95% CI = .91–1.02).

Table 3.

Negative Binomial Regressions Predicting Delinquency.

	Model 1			Model 2
	IRR	SE	95% CI	IRR	SE	95% CI
Maturity gap	1.10**	.02	1.06–1.14	1.11**	.02	1.07–1.15
Age puberty began	.96	.02	.91–1.02	.96	.02	.91–1.02
Days drink alcohol	1.07**	.01	1.04–1.11	1.06**	.01	1.03–1.09
Alcohol using peers	1.20**	.04	1.11–1.30	1.21**	.05	1.12–1.31
ASVAB	.99**	.01	.98-.99	.99**	.01	.98–99
Family income	.94*	.05	.90-.98	.95*	.05	.89–98
Age	.97	.05	.87–1.08	.96	.05	.86–1.08
Race	1.07	.03	1.00–1.13	1.07	.03	1.01–1.14
Maturity gap × days drink alcohol	-	-	-	.97*	.01	.96-.99
Wald χ2 (df)	167.72** (9)			236.55** (10)
N	1,276			1,276

Notes: IRR = incident rate ratio; SE = standard error; CI = confidence interval. **p < .01; *p < .05.

Model 2 shows the results from a second negative binomial regression model with an interaction term specified between the maturity gap and alcohol use included. The interaction term was negative and statistically significant (IRR = .97; 95% CI = .96–.99), indicating that the positive relationship between the maturity gap and delinquency was weaker at higher levels of alcohol use. A simple slopes analysis was conducted to further inspect this interaction. The results for participants who had positive scores on the measure of the maturity gap (indicating that they were caught in the gap) are presented in Figure 1. While males who scored 1 SD above the mean on alcohol use were more likely to report engaging in delinquency, compared to those at the mean and 1 SD below, these effects diminished as the maturity gap increased. Pairwise comparisons of average marginal effects were calculated to assess if any of the effects were significantly different from one another. In line with the presented overlapping 95% CIs in Figure 1, none of the effects were significantly different (1 SD below vs. 1 SD above = .03, 95% CI: −.009–.08; 1 SD above vs. Mean = .02, 95% CI: −.005–.05; Mean vs. 1 SD below = .01, 95% CI: −.003–.03). The interaction was further evaluated to identify where exactly the threshold was for the interaction where the number of times consuming alcohol fully attenuated the significant effect of the maturity gap on delinquency. The results from the analysis revealed that males who reported consuming, on average, 2.81 drinks or more in the last month did not report significantly higher levels of delinquent behavior, compared to those who consumed less alcohol.

Figure 1.

Marginal effects of the maturity gap for delinquency across levels of alcohol use.

Sensitivity Analysis

Following the primary analysis, a series of sensitivity regression models were estimated to evaluate whether and to what extent the association between the maturity gap and delinquency varied across participant age. The full sample was therefore disaggregated into samples of 12-, 13-, and 14-year-olds. The findings revealed that the maturity gap was more strongly associated with delinquency among 12-year-old males (IRR = 1.13, p < .001) than 13-year-old (IRR = 1.10, p < .001), and 14-year-old (IRR = 1.08, p = .086) males. However, there was no evidence of moderation by alcohol use on the relationship between the maturity gap and delinquency in any age group (results available upon request), which may have been due to the loss of sample size and statistical power for this type of analysis.

Discussion

Moffitt's (1993) maturity gap thesis may provide an explanation for the age-crime curve observed in AL offenders. This explanation may be further strengthened by considering alcohol use among this sample. As such, this study aimed to expand on previous literature by assessing the unique and interactive relations between the maturity gap, alcohol use, and delinquency among adolescent males. It was hypothesized that those who are caught in the maturity gap would be more likely to engage in delinquent behaviors. Additionally, it was hypothesized that those who use alcohol more frequently would report engaging in greater amounts of delinquent behavior. However, based on evolutionary arguments, it was predicted that those who were caught in the maturity gap and more frequently used alcohol, would be less likely to engage in other forms of delinquency. These hypotheses were based on previous literature suggesting that alcohol use may be a trait selected for its ability to increase social interactions and strong peer relationship formation and ease the tension of the maturity gap for those who display relatively higher levels of antisocial behavior tendencies (Gerald & Higley, 2002).

The present findings offer support for our first hypothesis. Participants who are caught in the maturity gap were more likely to engage in delinquent behavior. This finding is not surprising given previous literature that has tested and supported Moffitt's (1993) maturity gap thesis (Barnes & Beaver, 2010). By establishing a measure of maturity gap by comparing biological maturity with social autonomy, we were able to determine if those caught in the gap engaged in differing levels of delinquency. This finding is further supported from studies that suggest low expression of the monoamine oxidase – A (MAOA) gene (housed on the X chromosome) is a strong predictor of antisocial behaviors particularly among males (Eme, 2013). Future studies may seek to further evaluate this relationship to determine if those who are caught in the maturity gap are more likely to express lower levels of MAOA than those who do not experience disparities between biological and social maturity.

Furthermore, we found support for our second hypothesis predicting that those who use alcohol more frequently will be more likely to engage in delinquency. This finding is in line with previous literature that suggests early alcohol consumption is related to a host of negative life (DeWit et al., 2000; Garofoli, 2020) and behavioral outcomes (Dijkstra et al., 2015; Masson & Windle, 2002). Moreover, alcohol use was significantly and negatively correlated with social maturity, suggesting that those with reduced social autonomy are more likely to engage in alcohol use. These findings may indicate that those who are granted fewer social freedoms may cope with related frustrations through consuming alcohol. These individuals may also be more likely to engage in delinquent behaviors, providing support for Moffitt's (1993) thesis that those caught in the gap engage in increased substance use and delinquency as methods of coping.

Finally, the current findings offered partial support for our third hypothesis. Specifically, the strength of the positive association between the maturity gap and delinquent offending weakened as alcohol use increased; however, results from simple slopes analyses suggest that this interaction should be interpreted with caution. A possible explanation for this finding may be derived from an evolutionary perspective. Specifically, those who display antisocial behaviors may use alcohol to increase social interactions with others, which can increase environmental fitness in humans (Gerald & Higley, 2002). Consuming alcohol in a safe setting with older peers may also provide adolescents an opportunity to model mature behaviors under supervision and reduce the need to engage in more serious forms of delinquency. The act of consuming alcohol in social settings may serve to close the gap between biological and social maturity, such that adolescents who use alcohol more frequently may be less likely to turn to more serious acts of antisocial behavior. Despite these findings, it should be noted that alcohol use in excess is considered to be toxic (Clites et al., 2023).

Though the potential for both mediation and moderation exist, a test of mediation was unfortunately not possible in this study, as establishing time order between variables used to assess the maturity gap and delinquency was not possible. Because mediation assumes a potential causal process whereby a mediator comes between an independent and dependent variable in time, analyses from this study can only evaluate the moderating effect of alcohol use. Beyond these methodological reasons, evaluating the moderating effects of alcohol use on the relationship between the maturity gap and delinquency is built upon Moffitt's (1993) theoretical framework. Moffitt (1993) identifies alcohol use as a potential snare that increases the likelihood that adolescents will experience difficulty desisting from delinquency. Moffitt (1993) and Kandel (1980) further indicate that alcohol use may be symbolic of independence to adolescents, and adolescents who use alcohol may do so to mimic the modeled behavior by adults. It may be that alcohol use then modifies the relationship between the maturity gap and delinquency, rather than cause that relationship. However, more longitudinal research is needed to better understand alcohol use as an intervening mechanism between the maturity gap and delinquency.

Findings from this study should be interpreted in light of a few limitations. First, this study uses a single measure of biological maturity by asking participants whether pubertal changes were underway. This measure may be strengthened by using parental reports, as well as more items asking participants further questions related to biological maturity. Specifically, capturing items related to brain maturation or biological aging may help to strengthen this measure of biological maturity. Second, a relatively small proportion of the sample report drinking alcohol with frequency. Because this sample includes participants during middle to late adolescence, however, this is not surprising. Future research should aim to extend these findings with data spanning from middle adolescence to late adolescence or early adulthood. Third, this study only includes a sample of young males, thus the effect of alcohol use and the maturity gap among young females remains unclear. Future studies may seek to include young females. Finally, time order could not be established due to the cross-sectional data used for the analysis. Future work should aim to disentangle the directional effects between changes in the maturity gap, alcohol use, and forms of delinquency.

Despite these limitations, this study is strengthened by using a large number of participants and including self-report and parent-report information about social maturity, as well as information regarding biological maturity to create a measure of the maturity gap. This study is further strengthened by controlling for alcohol using peers, as Moffitt (1993) predicts that ALs may mimic the behaviors of LCPs in efforts to cope with the maturity gap they experience, as LCPs seem to cope more effectively. Life-course-persistents are often characterized as individuals who engage in more frequent alcohol consumption than their peers (Moffitt, 1993) and may influence ALs to similarly engage in greater drinking behaviors. By controlling for alcohol using peers, we are able to account for these potential influences in our models.

Future studies may seek to build off these findings by estimating the influence of alcohol use and the maturity gap on delinquency across a greater time span. Previous studies suggest that those who are caught in a maturity gap for longer periods of time may engage in greater amounts of delinquency (Negriff & Trickett, 2010). It may be that those who experience this maturity gap at an earlier age and consume alcohol earlier, may be more likely to engage in escalating amounts of delinquency over time. Further, future work may seek to assess whether interactive effects of alcohol and the maturity gap influence specific crime types. The current study used a variety index measure of delinquency, therefore the effect of the maturity gap and alcohol use on specific dimensions or types of delinquency remains unclear. Finally, future work may seek to uncover potential bidirectional relationships between the maturity gap and alcohol use. Dijkstra et al. (2015) indicate that parental conflict resulting from biological and social maturation discontinuity relates to increased delinquency and alcohol use. There is potential then, for alcohol use and the maturity gap to interact in a bidirectional manner.

Conclusion

Findings from this study suggest that early alcohol use moderates the relationship between the maturity gap and delinquency among a sample of U.S. males. The independent effects of the maturity gap on self-reported delinquency offer additional empirical support for Moffitt's (1993) maturity gap thesis. Based on reported findings situated within an evolutionary framework, alcohol use may serve as a buffer between the maturity gap and delinquent involvement in males in that it increases social interactions between those with little social autonomy, potentially closing the gap and reducing the need to rely on senseless acts of serious theft or violent behavior.