Discrimination of half-siblings when maternal genotypes are known

Given the DNA profiles of two individuals and one parent (say the mother) of each, we present likelihood ratios (LRs) comparing the hypothesis that they have the same father with the hypothesis of unrelated fathers. If the individuals have the same mother, the problem is to distinguish full- from half-siblings, otherwise we are comparing a half-sibling relationship with unrelated. We simulate STR profiles at up to 60 loci, based on allele proportions observed at 15 loci in three populations, and use them to approximate misclassification rates both for binary classification (e.g. "half-sib" versus "unrelated"), and when a third "cannot say" category is included. We find that reliable inferences in the absence of the mothers' profiles require many more STR loci than the 10-25 loci that are currently routinely available. However, profiling the two mothers conveys more discriminatory power than profiling the same number of additional loci in the individuals themselves. Our likelihood ratio formulas include a theta (or Fst) adjustment to allow for the individuals concerned to have recent shared ancestry (coancestry), relative to the population from which the allele frequency database is drawn. We illustrate that using an appropriate value of theta can reduce the average misclassification rate.     

Hispanic perception of police performance: An empirical assessment

This exploratory study examines relationships between the police and Hispanics in Texas. Specifically, data were collected on Hispanic evaluations of police performance, expectations of police performance, and overall satisfaction with the police. A sample of 500 Hispanics throughout the state of Texas were surveyed on their experienced and perceived relationships with three levels of police agencies: local (municipal) police, sheriff's officers, and the state's Department of Public Safety. Findings are reported based upon overall ratings of the police, victim-related data, and data from individuals who had any form of contact with the police. Significant findings show that any form of contact with the police appeared to lower the rating of police performance. This appears to be a product of the interaction between high public expectations and qualitatively poor police performance. Further findings indicate that an increase in the fear of crime among Hispanics lowered evaluations of local police. Similarly, victimization lowered the evaluation of local police, the county sheriff, and the Department of Public Safety. Hispanics also perceived that officers have a “bad attitude,” that the police need to patrol and investigate more, that response time should be improved, and that there should be less discrimination against Hispanics. These findings appear to be largely influenced by ineffective communication (both symbolic and linguistic) and cultural conflict.     

Competency-based education: An alternative for criminal justice education?

Over the last several years, criminal justice education In the United States has increased dramatically. Much of this growth has been in response to the needs of an evolving criminal justice field. However, there is some concern among professionals that the criminal justice system needs to be impacted more directly, and that institutions of higher learning need to be impetus for this change. To complete this task, curricula in higher education programs need to become more relevant to the needs of the system, while not ignoring the student of the educational system. This article examines the use of competency-based education (CBE) as a model that will serve the criminal justice student of today and the criminal justice system of tomorrow.