1. Use of Data for High-Impact Research: Three Case Studies Brian Forst School of Public Affairs – Department of Justice, Law & Criminology Conference for High Impact Research Session on Sharing Research Data for Accessibility and Reusability American University May 15, 2017

2. The Three Case Studies What happens after arrest?
Study of prosecution using the PROMIS data,
What are the sources of mass incarceration?
Analysis of the sources of escalating incarceration rates,
Is terrorism in the name of Islam underreported?
Analysis of biases in open source reporting

3. What happens after arrest?
Cases fail not so much because of police violations of due process, as had been widely believed. They fail primarily because of weaknesses in tangible evidence and poor witness support, and because some police officers are much less effective in bringing strong cases -- arrests that end in conviction -- at systematically lower rates than those brought by other officers.
Prosecution differs substantially from place to place in at least one basic regard: the preference for pleas or trials. Plea-to-trial ratios vary from 4 or 5 to 1 in jurisdictions aiming for quality convictions to over 25 to 1 in those aiming for more convictions. Jurisdictions that aim for quality tend to screen out cases brought by police at a much higher rate than those that aim for more convictions.
A rare opportunity to test the Prisoners Dilemma in the field by comparing plea rates in solo- and co- defendant robbery cases that ended in conviction found no tendency for prosecutors to extract pleas at a higher rate from co-defendant cases than solo defendant cases, controlling for other factors. Real-world offenders impose sanctions on one another that tend to have more impact on their willingness to cooperate with the prosecutor than is recognized in the Prisoner's Dilemma.

4. What are the sources of mass incarceration?
High incarceration rates in the U.S. have been widely attributed to draconian drug laws and overly long sentences.
From 1992 to 2002 the reported offense rates of major categories of crime -- homicide, rape, robbery, burglary, and assault -- declined by about half, while the prison population increased substantially, both absolutely (by 61%) and as a percentage of the resident U.S. population (41%).
Gross incarc’n rate = Offending rate  Reporting rate  Arrest rate  Conviction rate  Incarc’n rate for convictees  Average term of incarceration
[Inmates/Pop’n = (Victimiz’ns/Pop)(Reported crimes/victimiz’ns)(Arrests/Reported crimes) (Convic’ns/arrests)(New incarc’ns/convic’ns)Avg term of incarc’n]
The incarceration rate and average sentence imposed for convicted drug offenders actually declined during the decade in question.
The gross incarceration rate increased primarily because prosecutors were convicting more people and because people imprisoned years earlier weren’t being released in large numbers.

5. Is terrorism in the name of Islam underreported?
We compared databases on terrorist incidents from open sources (assembled, organized and maintained in the START project's Global Terrorism Database) with those reported in official sources in Turkey from 1988 to 2012 to examine the extent of over- or under-reporting of incidents in the media.
In sharp contrast to the assertions from the White House, we found that terrorist attacks reported by the Turkish National Police were four to five times more likely to show up in open sources -- media accounts -- if the attacks were religiously motivated. Controlling for other factors, including the severity of the attack and other factors reflecting newsworthiness, religiously motivated attacks were about twice as likely to be reported in open sources.

6. References
Shawn Bushway and Brian Forst, "Studying Discretion in the Processes that Generate Criminal Justice Sanctions," Justice Quarterly, Volume 30, Issue 2 (2013), pp
Suat Cubukcu and Brian Forst, “Playing Fast and Loose with the Reporting of Terrorism,” Political a Glance (February 15, 2017)
Brian Forst, "The Prisoner's Dilemma: Theory and Reality," Journal of Criminal Justice, vol. 5 (Spring 1977)
Brian Forst, "Prosecution," in Crime and Public Policy, James Q. Wilson and Joan Petersilia, editors (New York: Oxford University Press, 2011)
Brian Forst and Kathleen Brosi, "A Theoretical and Empirical Analysis of the Prosecutor," Journal of Legal Studies, vol. 6 (January 1977)