PROBABILISTIC MODELS OF YOUTHFUL CRIMINAL CAREERS

This paper focuses on the characterization of the criminal careers of youthful offenders. It was found that these criminal careers could be modeled with parameters rejecting constant individual rates of offending and constant probability of career termination; population heterogeneity could be adequately represented by two distinct groups—designated here as "frequents" and occasionals." These parameters were estimated for the multiple offenders in a London cohort studied from their first convictions until age 25. In that cohort, the frequents were estimated to have an annual conviction rate of 1.14 convictions per year (constant with age) and a probability of career termination of .10 following each conviction; the occasionals had an annual conviction rate of .41 and termination probability of .33 following each conviction; the frequents were estimated to comprise 43% of the population, and the occasionals the others 57%. While this parsimonious model structure was adequate for the London cohort, it must still be tested with other offender populations.     

MODELING CRIMINAL CAREERS*

A stochastic model of criminal careers embodying the assumptions of Gottfredson and Hirschi (1986, 1988) is used as a tool to examine the arguments and claims that have been raised in the recent debate over the nature of criminal careers. The model is used to fit aggregate career data in different jurisdictions and to explain racial and sex patterns in recidivism data. Some of the arguments that have been deployed on both sides of this debate are shown to lack validity. Nullius in verba. —Motto of the Royal Society     

AN EXPLORATORY STUDY OF SUPERVISED ACCESS AND CUSTODY EXCHANGE SERVICES

An exploratory outcome study to investigate the ability of a supervised access and custody exchange center to function as a safe visitation enforcement mechanism of the court was accomplished as part of a larger study investigating child well-being. During a 6-month period of program participation, frequency and consistency of noncustodial parents' access to children dramatically increased and interparental conflict significantly decreased, demonstrating that supervised visitation and custody exchange centers that function in partnership with family court during interim court processes can address the unmet needs of family court and high-conflict domestic disputant as well.     

ASSESSMENTS OF RISK AND BEHAVIORAL EXPERIENCE: AN EXPLORATORY STUDY OF CHANGE

This study examines the relationship between assessments of the risk of punishment and self-reported involvement in three illegal behaviors in a sample of college-aged respondents. It is found that those respondents who had not yet committed a particular offense were more likely to perceive a greater certainty of punishment than those with experience in committing the offense. For two of three offenses the effect of becoming involved in offending had a more substantial impact on the perceptions of those respondents with both experience in offending and high perceived certainty of punishment than on those who had experience and less pessimistic estimates of risk Finally, a multivariate analysis of the relationship between behavioral and perceptual change reveals that each variable affects the other even when other sources of change are controlled. The importance of the findings for the deterrence doctrine are discussed.     

A LATENT TRAIT APPROACH TO UNIFYING CRIMINAL CAREERS *

We propose a latent trait model that simultaneously accounts for both participation in crime and the frequency of crimes, phenomena that the criminal career model attributes to different causal processes. The criminal career model is predicated on a categorical distinction between active offenders and nonoffenders, but the latent trait model assumes a continuous distribution of propensity to offend. Our specific statistical model relates a relatively stable and general latent propensity to engage in crime to the frequency of criminal behavior. The latent trait model successfully fit both the proportion of offenders (participation) and frequency of offending for several samples and several measures of offending. The model fit both samples of whites and nonwhites and both males and females. This shows that separate causal processes are not necessary to account for group differences in frequency and in participation, which disproves the major evidence in favor of the criminal career model. Finally, the latent trait model yielded evidence that disparate sex differences in rates of participation for different categories of offenses are consistent with a single difference on a latent trait. This demonstrates the latent trait model's potential for parsimoniously unifying knowledge about criminal careers.     

PARTICIPATION AND FREQUENCY DURING CRIMINAL CAREERS ACROSS THE LIFE SPAN*

Recent advances and debates surrounding general and developmental as well as static and dynamic theories of crime can be traced to the 1986 National Academy of Science's Report on criminal careers and the discussion it generated. A key point of contention has been regarding the interpretation of the age–crime curve. According to Gottfredson and Hirschi (1986), the decline in the age–crime curve in early adulthood reflects decreasing individual offending frequency (λ) after the peak. Blumstein et al. (1986) claimed that the decline in the aggregate age–crime curve also could be attributable to the termination of criminal careers, and the average value of l could stay constant (or increase with age) for those offenders who remain active after that peak. Using data from the Criminal Career and Life Course Study—including information on criminal convictions across 60 years of almost 5,000 persons convicted in the Netherlands—and applying a two-part growth model that explicitly distinguishes between participation and frequency, the study outlined in this article assessed the participation–frequency debate. Results suggest that the decline in the age–crime curve in early adulthood reflects both decreasing individual offending participation and frequency after the peak, that the probabilities of participation and frequency are significantly related at the individual level, and that sex and marriage influence both participation and frequency.     

AN EXPLORATORY STUDY OF THE VIOLENT VICTIMIZATION OF WOMEN: RACE/ETHNICITY AND SITUATIONAL CONTEXT*

Although much has been learned in recent years about the victimization experiences of women, there remains a considerable knowledge gap with respect to the victimization of women of different racial and ethnic backgrounds. In order to confront this issue, we use the large number of cases available in the National Crime Victimization Survey (1992–2000) to examine the risk and protective factors associated with violent victimization among non‐Hispanic white, non‐Hispanic black, Hispanic, Asian/Pacific Islander, and Native American women. We then describe in more detail the violent incidents against these women, looking for distinguishing patterns across groups. Our results are useful for fine‐tuning theories of victimization to explain variance in violence for females across racial and ethnic subgroups.     

BRIDGING CRIMINAL CAREERS,THEORY, AND POLICY THROUGH LATENT VARIABLE MODELS OF INDIVIDUAL OFFENDING*

Our goal is to build bridges between theoretical criminology, the study of criminal careers, and policy-relevant research. Insights from the criminal career and propensity positions lead us to seek (1) a comprehensive means of incorporating theoretical variables in research on criminal careers, (2) statistical models that yield meaningful projections relevant to public policy issues, and (3) methods for comparing findings for different measures of offending. We present a conceptual framework accomplishing this by applying the general linear model to the study of crime and criminal careers. This framework differentiates the elements of (1) a curvilinear function linking the scale of the linear model and the scale of the measure of offending, (2) a probabilistic relationship between a latent tendency to offend and the measure of offending, (3) a probability distribution of individual differences on the latent dimension, and (4) relationships among repeated observations for the same individual. We describe numerous versions of the general linear model that do not require special statistical expertise and are appropriate for the full range of measures of offending. We conclude by addressing strategies for comparing results across measures.     

溺死家兔内脏花粉检验的研究

用醋酸酥法破机，显微镜下观察内脏组织中花粉。12只溺死家兔的肺边缘组织检出率为100％（肺组织含花粉500粒／g左右），肝为50％，肾为33．3％；溺死后1天，1周、2周三组解剖，肺边缘组织花粉计数值无明显差异，证明花粉具有很强的抗腐败能力，可以作为水中高度腐败尸体死因鉴定依据之一。同时，水体沉积物花粉港能够反映入水地点的植被状况，为判断和认定溺死者的入水地点提供依据；此法尤其适用于冰水等硅藻和浮游生物很少的水体中的生前入水溺死的诊断。     

THE STABILITY OF CRIMINAL POTENTIAL FROM CHILDHOOD TO ADULTHOOD*

This paper examines two alternative interpretations of the well-documented positive association between past and future criminal behavior. One is that prior participation has a genuine behavioral impact that increases the likelihood of future participation. The second is that there are stable, unmeasured differences in criminal potential across the population. Many general theories of crime can be interpreted as suggesting one of these interpretations. Based on an analysis of a panel data set that tracks a sample of males for over 20 years, the results suggest that the positive association is largely attributable to stable, unmeasured individual differences.     

DIFFERENTIAL CRIMINAL PATTERNS OF NARCOTIC ADDICTS OVER AN ADDICTION CAREER*

In a further study of the addiction-crime relationship, 214 narcotic addicts were classified according to their criminal involvement during a 2-year preaddiction period. The sample was divided into two groups—those who reported involvement in any of 20 categories of criminal activity (N = 108) and those who reported no such activity (N = 106). The criminal behavior and drug-use patterns of the two groups were then compared during subsequent addiction and nonaddiction periods. As expected, the impact of addiction was much more prominent in the low-crime group. The implications of results for rehabilitation strategies are discussed.     

AGE,CRIMINAL CAREERS,AND POPULATION HETEROGENEITY: SPECIFICATION AND ESTIMATION OF A NONPARAMETRIC,MIXED POISSON MODEL*

This article addresses three issues that are central to the criminal career debate. First, is the life course of individual offending patterns marked by distinctive periods of quiescence? Second, at the level of the individual, do offending rates vary systematically with age? In particular, is the age-crime curve single peaked or flat? Third, are chronic offenders different from less active offenders? Do offenders themselves differ in systematic ways? Using a new approach to the analysis of individual criminal careers—based on nested, mixed Poisson models in which the mixing distribution is estimated nonparametrically—we analyze a panel data set that tracks a sample of males for more than 20 years. Our results provide empirical evidence in support of some features of criminal propensity theory and some in support of conventional criminal careers theory. In support of latent-trait criminal propensity theory, the individual-level average offense rate (per unit of time) varies as a function of observable individual-level characteristics and unobservable heterogeneity among individuals, and the age trajectory of the offense rate is generally single peaked rather than flat. On the other hand, in support of conventional criminal careers theory, models that incorporate a parameter that permits periods of active as well as inactive offending across age have greater explanatory power than those that do not. In addition, the nonparametric, discrete approximation to the population distribution of unobservable heterogeneity in the individual-level mean offense rate facilitates identification of four classes of offenders—nonoffenders as well as individual-level characteristics that are unique to each group. Problems of theoretical explanation and empirical generalizability of these results are described.     

SELF-CONTROL IN A CRIMINAL SAMPLE: AN EXAMINATION OF CONSTRUCT VALIDITY*

Favorable evidence on the validity of the Grasmick et al. (1993) self-control scale has been reported in studies using general population samples. However, the scale has never been tested among persons extensively involved in crime. We assessed the construct validity of this scale, slightly revised, in a heterogeneous sample of drug-using criminal offenders. Factor analyses identified five subscales, mostly congruent with existing formulations of the self-control construct. Also, recent crimes of force and fraud were more frequent among people scoring lower on self-control. However, the five-factor solution was not tenable among women, and the scale was no more closely related to crime than were three subscales representing more specific constructs already established in criminology.     

THE TRUE VALUE OF LAMBDA WOULD APPEAR TO BE ZERO: AN ESSAY ON CAREER CRIMINALS,CRIMINAL CAREERS,SELECTIVE INCAPACITATION,COHORT STUDIES,AND RELATED TOPICS*

The idea of selective incapacitation and the distinction between prevalence and incidence (participation and lambda) justify the search for a group of offenders whose criminality does not decline with age and who may be identified solely on the basis of legally relevant variables. This paper questions such research, arguing that the decline in age with crime characterizes even the most active offenders. and that the distinction between incidence and prevalence does not deserve the theoretical, research, or policy attention it has been claimed to merit (Farrington, 1985; Blumstein and Graddy, 1981–1982). In doing so, it relies on research results widely accepted in criminology. Thus, the current focus of criminological research on the “career criminal,” on selective incapacitation, and on longitudinal research remains unjustified.     

CRIMINAL BEHAVIOR AND THE GAINS FROM CRIME

A number of economists recently have applied tools of economics to analysis of crime. The resulting models of criminal activity typically postulate that crime is positively related to gains porn crime and inversely related to the probability of punishment. While empirical studies have confirmed this latter effect, the relation between gains from crime and criminal activity has not been satisfactorily examined. This paper specifically tests the empirical relation between criminal behavior and the gains from crime. The unsettling possibility that decreases in the gains from crime my lead to increases in the number of crimes is discussed.     

NONSOCIAL REINFORCEMENT AND HABITUAL CRIMINAL CONDUCT: AN EXTENSION OF LEARNING THEORY *

Drawing on a diverse literature, we explain how criminal behavior is maintained through a process of nonsocial reinforcement, and show that some persons find criminal behavior particularly rewarding. We test our assumptions using surveys of 295 incarcerated adult felons and 150 male college students and intensive focus groups with 40 habitual offenders currently serving time. Results suggest that the experience of committing nonviolent and, particularly, violent crime is intrinsically rewarding and tends to reinforce such behavior among habitual criminals. The endogenous rewards identified center on (1) the neurophysiological high such acts produce and (2) the symbolic meaning of the behavior as it relates to self-concept and identity formation. Findings from the surveys and the focus groups suggest that habitual criminality is sustained partly through the positive sensations (physiological and psychological) those crimes activate within the offender and that those sensations are instrumental in the maintenance and reinforcement of criminal careers. Based on what is known in the literature and what has been learned from our research, it seems that an effective way of integrating this knowledge lies in the direction of a nonsocial reinforcement arm of learning theory.