According to Liptak, Justice Scalia believes that

The rate at which innocent people are convicted of felonies is, he said, less than three-hundredths of 1 percent — .027 percent, to be exact. That rate, he said, is acceptable. “One cannot have a system of criminal punishment without accepting the possibility that someone will be punished mistakenly,” he wrote. “That is a truism, not a revelation.”

But that rate is based on a false number, failing to account for the potential innocents convicted for crimes other than murder and rape who are subsequently exonerated by DNA.  For somewhat obvious reasons, one cannot use the absolute number of DNA exonerations, 214 at this writing, and divide by the total number of all felony convictions.  Well, you can, but you end up with a totally wrong number.

Liptak takes this application of math to show that we don’t know, and can’t say, how many innocents are convicted.

What the debate demonstrates is that we know almost nothing about the number of innocent people in prison. That is because any effort to estimate it involves extrapolation from just two numbers, neither one satisfactory.

We are left with an uneasy agreement between Professor Gross and Mr. Marquis on at least one point. “Once we move beyond murder and rape cases,” Professor Gross wrote, “we know very little about any aspect of false conviction.”

While it is a truism that we cannot know with precision, particularly in a system that involves so many variables as criminal justice, the real number of “casualties”, I suspect we can do a whole lot better than Liptak does, and that his willingness to give up so easily is a disservice to an important topic.

There are at least five prominent sources of wrongful convictions:

• Mistaken eyewitness identification


• Perjurious testimony (testilying)


• False confession


• Racial influence


• Guilty pleas of convenience

If we look to the cases where innocence is subsequently determined by DNA evidence, in order to use a hard measure to determine a factually wrongful conviction, and then go back to the basis upon which the conviction was obtained, we can then extrapolate statistically the percentage of the total conviction rate, based upon the mechanism of conviction, of innocent people.

But a few general lessons can be drawn nonetheless. Black men are more likely to be falsely convicted of rape than are white men, particularly if the victim is white. Juveniles are more likely to confess falsely to murder. Exonerated defendants are less likely to have serious criminal records. People who maintain their innocence are more likely to be innocent. The longer it takes to solve a crime, the more likely the defendant is not guilty.

So do we accept the premise that the system isn’t perfect, something we know to be true, and just shrug off the question of whether the number of innocent people wrongfully convicted of crimes is an “acceptable” number of casualties in the war against crime, or do we try to do better, think a little harder, and come up with numbers that have some real bearing on the problem? 

Without this number, the degree of “imperfection” in the criminal justice system is too abstract to disturb most people about how well or poorly our system works.  People don’t get too concerned over abstractions, unless it happens to hit them where they live.  As my good buddy Mike from the train tells me, “Hey, somebody has to take one for the team, as long as it isn’t one of mine.”  I suspect most people feel that way in their hearts.

Liptak settles far too easily.  But then, neither he nor any of his loved ones are sitting in a prison cell.