More on the Wrongful Conviction Rate

Samuel R. Gross, the Thomas and Mabel Long Professor of Law at the University of Michigan, writes in today's LA Times:

If 1% of commercial airliners crashed on takeoff, we'd shut down every airline in the country. That would be nearly 300 crashes a day. If as few as 1% of criminal convictions are erroneous, right now there are more than 20,000 innocent defendants behind bars.

But 1% seems like a low number based upon his research. At least 3.3% of those convicted of murder were innocent. How many were wrongly convicted of lesser crimes for which there is less scrutiny? How many innocent people, fearing the possibility of a wrongful conviction, much less the wanting to avoid the expense of a trial or time lost while unable to make bail, have copped pleas? How much are we paying to incarcerate the innocent?