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Since 1970, legislatures have increasingly relied on preventive detention – detention before trial ordered solely to prevent an accused from committing crime during the pretrial period – as an instrument of social control. Prior to this period, detention before trial was usually ordered only to assure an accused's presence at trial or to ensure the integrity of the trial process by preventing an accused from tampering with witnesses. Today, the majority of states and the federal system have changed their laws to allow judges to detain arrestees who pose a risk to society if released during the pretrial period. Half of these laws were passed in the 1980's.

The significant increase in the use of detention before trial to prevent crime has not occurrred without debate and legal challenge. Two U.S. Supreme Court decisions in the 1980s ensured that preventive detention would continue to be part of legal proceedings in criminal courts throughout the country. Schall v. Martin upheld a New York statute authorizing the preventive detention of juvenile delinquents, and United States v. Salerno upheld the federal Bail Reform Act of 1984 which authorized the use of preventive detention in federal criminal prosecutions. Although the Supreme Court in both cases rejected the use of detention before trial for punitive purposes, it approved its use as a non-punitive regulatory governmental power to prevent future crimes and thereby advance state objectives to protect community safety. Thus, the degree to which preventive detention furthers its community safety purpose depends entirely upon the capacity to predict who will commit a crime over a specified period of time. These short-term predictions of dangerousness are made for defendants awaiting further court appearances. Both Schall and Salerno challenged the use of preventive detention on the ground that the prediction capacity is too poor to justify its use, but these challenges were squarely rejected. In both cases, the Court concluded that predictions of dangerousness were not so unreliable as to pose due process or equal protection concerns. In Schall, the Court emphasized that "there is nothing inherently unattainable about prediction of future criminal conduct"; it also acknowledged that the prediction of future criminal conduct is "an experienced prediction based on a host of variables which cannot be readily codified." However, the validity official predictions of dangerousness is unknown, and the consequences of false predictions of future crimes remain the hidden cost of preventive detention. The predictive validity of judicial determinations of dangerousness inherent in preventive detention is the focus of this research.


Juvenile Law | Law | Supreme Court of the United States