[2] Tonry has researched various subjects in the field of criminal law, including the increasing incarceration rate in the United States during the late 20th century.
[4][5] In his 1995 book Malign Neglect: Race, Crime and Punishment in America, he acknowledged that racial disparities in the criminal justice system are mainly due to differences in criminal activity among races, but also found that the proportion of people arrested for murder, rape, robbery and aggravated assault who were black had remained constant at about 45% since the mid-1970s.
[6] However, in a 2008 article in Crime and Justice with Matthew Melewski, Tonry found that a disproportionate number of racial minorities are incarcerated in part because sentencing policies have a disparate impact on those groups.
[10] He supports non-prison punishments for nonviolent offenders, but has acknowledged that the United States' prison population increasing to almost 2 million people (as of 1998) had reduced crime.
That year, he told Eric Schlosser that "You could choose another two million Americans at random and lock them up, and that would reduce the number of crimes too.