The grizzled, world-weary detective who solves tough cases on a hunch is a staple of TV and movie crime dramas.
But statistics tell a very different story about the achievements of real-life crime sleuths.
“Clearance rates”—the percentage of solved crimes—for murder and other serious offenses have been plummeting at least since 1960; and disclosures of wrongful arrests have added more fuel to fiery critiques of the justice system.
Much of the national attention to justice mistakes has focused on wrongful convictions that send innocent individuals to prison—or in some cases to Death Row. But a growing body of scholarship has begun to examine why criminal investigations can go so badly wrong at the “gateway” to the system.
“The consequences of investigative failure are huge,” said D. Kim Rossmo, a criminologist at Texas State University, noting that sending the wrong individual to prison for murder means the real killer is still at large.
Rossmo, who chaired a discussion entitled “The New Detective: Rethinking Criminal Investigations” at the American Society of Criminology’s annual conference in San Francisco Thursday, suggested that “thinking errors” were among the principal afflictions of crime investigators.
Detective work can be influenced by pressure from the public, the media, or local prosecutors to crack a controversial case quickly, and that in turn often persuades investigators to rely on evidence that appears to corroborate their assumptions or “hunches,” Rossmo said.
Instead, detectives should check just as hard for evidence that might clear a suspect as they do for evidence of his guilt, he suggested.
“We tend to regard significant evidence as important even when its reliability is low,” he said. “Evidence is not sufficient to solve a crime, even if it is significant.”
The only way to correct for common errors such as “confirmation bias,” defined as seizing on facts that confirm your hunches, is to constantly question what seems like unshakable proof of guilt—a witness identification, a fingerprint at the murder scene, a cut-and-dried motive—and look just as hard for evidence that might demonstrate the innocence of the accused, he said.
“It doesn’t matter how good our technology is,” said Rossmo. “If we have flawed thinking, it undermines judgment.”
A similar approach had been urged on prosecutors, as a way of avoiding the kinds of tragedies that result from wrongful convictions.
But rethinking the role of detectives may also involve looking beyond the investigative process.
John Eck of the University of Cincinnati noted that the decline in clearance rates coincided with significant drops in the U.S. crime rate, raising the question of whether “solving crime (is) unrelated to reducing crime.”
Eck, the co-author with Kim Rossmo of the study showing the 40-year drop in solved crimes, said his work should persuade law enforcement to focus not only on the quality of police investigations but also on crime prevention.
In areas where crime rates have bucked the national trend—in cities for instance where homicides have spiked—investigators and policymakers should be looking at the “crime-facilitating circumstances,” such as poor schools, decaying housing, and high poverty rates.
Another panelist, former Los Angeles Times reporter Jill Leovy, author of “Ghettoside,” the bestselling account of the Los Angeles Police Department, said her own investigations showed that even before the 1960s, clearance rates in L.A. were massaged to provide misleading versions of crime investigations.
“It’s a problem that goes back 100 years,” she said.
A fourth speaker, Brian Forst of American University, called on policymakers to reexamine their general assumptions about the proactive crime-fighting strategies that have been in favor over the past decades, such as “intelligence-led” policing and “hot spot” policing, because they were as likely to lead to wrongful arrests as to increased public safety.
Wrongful arrests arise from errors of “due process” or impunity—over-aggressive policing that places the goal of getting a suspected dangerous individual off the street ahead of the possibility that he may be innocent, Forst said.
Many prosecutors’ offices are already shifting to a focus on identifying the kinds of systemic errors that have led to miscarriages of justice, using tools such as “conviction integrity units.”
The approach, modeled on analytical strategies long used in medicine and aviation to understand why tragedies occur, is usually described as “Sentinel Event” thinking, and has been adopted by the Department of Justice in several pilot projects around the country.
Detectives should be trained in the same approach, suggested Forst.
“A system of accountability should be in place to help detectives think more about error management than clearance rates,” he said.
“Miscarriages of justice harm us all, and undermine the legitimacy of our system of justice. They deserve more thought than we have given them so far.”
Stephen Handelman is editor of The Crime Report.