Brian D. Johnson

Tree-maps: a space-filling approach to the visualization of hierarchical information structures

A method for visualizing hierarchically structured information is described. The tree-map visualization technique makes 100% use of the available display space, mapping the full hierarchy onto a rectangular region in a space-filling manner. This efficient use of space allows very large hierarchies to be displayed in their entirety and facilitates the presentation of semantic information. Tree-maps can depict both the structure and content of the hierarchy. However, the approach is best suited to hierarchies in which the content of the leaf nodes and the structure of the hierarchy are of primary importance, and the content information associated with internal nodes is largely derived from their children.<<ETX>>

Improving the visualization of hierarchies with treemaps: design issues and experimentation

Controlled experiments with novice treemap users and real data highlight the strengths of treemaps and provide direction for improvement. Issues discussed include experimental results, layout algorithms, nesting offsets, labeling, animation, and small multiple displays. Treemaps prove to be a potent tool for hierarchy display. The principles discussed are applicable to many information visualization situations.<<ETX>>

CUMULATIVE DISADVANTAGE: EXAMINING RACIAL AND ETHNIC DISPARITY IN PROSECUTION AND SENTENCING

Current research on criminal case processing typically examines a single decision-making point, so drawing reliable conclusions about the impact that factors such as defendants’ race or ethnicity exert across successive stages of the justice system is difficult. Using data from the New York County District Attorneys Office that tracks 185,275 diverse criminal cases, this study assesses racial and ethnic disparity for multiple discretionary points of prosecution and sentencing. Findings from multivariate logistic regression analyses demonstrate that the effects of race and ethnicity vary by discretionary point and offense category. Black and Latino defendants were more likely than White defendants to be detained, to receive a custodial plea offer, and to be incarcerated—and they received especially punitive outcomes for person offenses—but were more likely to benefit from case dismissals. The findings for Asian defendants were less consistent but suggest they were the least likely to be detained, to receive custodial offers, and to be incarcerated. These findings are discussed in the context of contemporary theoretical perspectives on racial bias and cumulative disadvantage in the justice system.

Trial Penalties in Federal Sentencing: Extra-Guidelines Factors and District Variation

The guarantee of the right to a jury trial lies at the heart of the principles that underlie the American criminal justice systems commitment to due process of law. We investigate the differential sentencing of those who plead guilty and those convicted by trial in U.S. District Courts. We first investigate how much of any federal plea/trial sentencing differences are accounted for by substantial assistance to law enforcement, acceptance of responsibility, obstruction of justice, and other Guideline departures. Second, we investigate how such differences vary according to offense and defendant characteristics, as well as court caseloads and trial rates. We use federal sentencing data for fiscal years 2000–02, along with aggregate data on federal district court caseload features. We find that meaningful trial penalties exist after accounting for Guidelines‐based rationales for differentially sentencing those convicted by guilty plea versus trial. Higher district court caseload pressure is associated with greater trial penalties, while higher district trial rates are associated with lesser trial penalties. In addition, trial penalties are lower for those with more substantial criminal histories, and black men. Trial penalties proportionately increase, however, as Guideline minimum sentencing recommendations increase. We also supplement our analysis with interview and survey data from federal district court participants, which provide insights into the plea reward/trial penalty process, and also suggest important dimensions of federal court trial penalties that we cannot measure.

Criminal Prosecutions: Examining Prosecutorial Discretion and Charge Reductions in U.S. Federal District Courts

The role of the prosecutor in criminal punishments remains a fervent topic of criminal justice discourse, yet it has received limited empirical attention, particularly for U.S. Attorneys in federal district courts. The present study examines charging and sentencing outcomes in federal courts by combining charging data from the Administrative Office of the U.S. Courts with sentencing data from the U.S. Sentencing Commission. The merger of these data sources overcomes limitations of each and provides for an investigation of the causes and consequences of federal prosecutorial charging decisions. Our investigation focuses on the subtle but important influences that extralegal offender characteristics exert in this process. Results indicate that some extralegal characteristics are intricately tied to the likelihood of charge reductions. Moreover, these effects sometimes interact to produce compound disadvantages for some groups of offenders. Our analyses are guided by contemporary theoretical perspectives on courtroom decision‐making.

TreeViz: treemap visualization of hierarchically structured information

Scientific visualization has received a great deal of attention in recent years. There are many reasons for this but chief among them is the simple observation that humans have difficulty extracting meaningful information from large volumes of data. Our increasing ability to produce, disseminate, and collect information has quite naturally led to a demand for tools which aid in the analysis of this information and support our intuition.

Multilevel Analysis in the Study of Crime and Justice

The study of crime and justice often involves the nesting of individual observations within larger social contexts of interest – juveniles are nested within schools, offenders within neighborhoods, police within precincts, judges within courts, inmates within prisons and so on. In these and related instances, multilevel models provide a useful extension of ordinary regression models that allow for the simultaneous inclusion of data across multiple units of analysis. This chapter provides a general introduction to the use of multilevel models, discussing the different forms they take and illustrating their basic application through the example of convicted offenders sentenced within federal district court contexts. The chapter concludes with a introduction and overview of some common difficulties and more complex modeling issues that sometimes arise in multilevel analysis.

Opening Pandora’s Box: How Does Defendant Race Influence Plea Bargaining?

Minority overrepresentation in the criminal justice system has long been an important topic of research and policy debate. In New York City, recent changes in the Rockefeller Drug Laws and the controversy around police stop-and-frisk practices have placed an even greater emphasis on the need for studying the possible impact of defendants’ race and ethnicity on criminal justice outcomes. Relatively little contemporary research, though, examines plea-bargaining outcomes. Using unique data on misdemeanor marijuana cases, this study examines the impact of defendants’ race on prosecutors’ decisions to make (a) plea offers for a lesser charge and (b) sentence offers for non-custodial punishments. Preliminary findings indicated that black defendants were less likely to receive reduced charge offers, and both black and Latino defendants were more likely to receive custodial sentence offers. However, these disparities were largely explained by legal factors, evidence, arrest circumstances, and court actor characteristics, though black defendants were still more likely to receive custodial sentence offers after including these controls. No differences were found between white and Asian defendants. Implications for research and prosecutorial practices are discussed.

Judges on Trial

Extant research on the effects of judicial background characteristics suggests minimal influence from the race or gender of the sentencing judge in criminal cases. This raises at least two possibilities: (1) the combined influence of judicial recruitment, indoctrination, and socialization into the judgeship results in a homogenous body of criminal court judges; or (2) current approaches to identifying judge effects in criminal sentencing have methodological and conceptual flaws that limit their ability to detect important influences from judicial background characteristics. The current article examines this issue with data from the Pennsylvania Commission on Sentencing that is augmented to include information on sentencing judges and criminal court contexts. It argues that the mode of conviction shapes the locus of sentencing discretion in ways that systematically underestimate judge effects for pooled estimates of incarceration and sentence length. The empirical results support this interpretation, especially for incarceration in trial cases, where older, female, and minority judges are substantially less likely to sentence offenders to jail or prison terms. The article concludes with a discussion of future research directions and policy implications for judge effects and disparity in sentencing.

Offender’s Personal Circumstances and Punishment: Toward a More Refined Model for the Explanation of Sentencing Disparities

Prior research suggests that offender sex, age, and race are often influential determinants of sentencing outcomes. According to focal concerns theory, they affect sentencing because—due to limited time and information—judges rely on stereotypical behavioral expectations when assessing offender blameworthiness and dangerousness. As such, extralegal offender characteristics may serve as proxies for more specific risk indicators. Whether more complete information on additional risk factors helps account for the effects of extralegal characteristics, however, remains an untested assumption. Therefore, this study analyzes the Dutch data on standardized pre-sentencing reports to examine the influence of personal circumstances of the offender, such as employment, family, and drug use factors, on the likelihood and length of incarceration. The results suggest that personal circumstances exert inconsistent influence over sentencing outcomes and that they fail to significantly mitigate the direct effects of sex and age, but do mitigate the effects of national origin.