Interesting New Yorker piece on why innocent people plead guilty to crimes in the United States:
In addition to mandatory minimums, Congress in 1984 introduced—with bipartisan support—a regime of mandatory sentencing guidelines designed to avoid “irrational” sentencing disparities. Since these guidelines were not as draconian as the mandatory minimum sentences, and since they left judges with some limited discretion, it was not perceived at first how, perhaps even more than mandatory minimums, such a guidelines regime (which was enacted in many states as well) transferred power over sentencing away from judges and into the hands of prosecutors.
One thing that did become quickly apparent, however, was that these guidelines, along with mandatory minimums, were causing the virtual extinction of jury trials in federal criminal cases. Thus, whereas in 1980, 19 percent of all federal defendants went to trial, by 2000 the number had decreased to less than 6 percent and by 2010 to less than 3 percent, where it has remained ever since.
. . .
Third, and possibly the gravest objection of all, the prosecutor-dictated plea bargain system, by creating such inordinate pressures to enter into plea bargains, appears to have led a significant number of defendants to plead guilty to crimes they never actually committed. For example, of the approximately three hundred people that the Innocence Project and its affiliated lawyers have proven were wrongfully convicted of crimes of rape or murder that they did not in fact commit, at least thirty, or about 10 percent, pleaded guilty to those crimes. Presumably they did so because, even though they were innocent, they faced the likelihood of being convicted of capital offenses and sought to avoid the death penalty, even at the price of life imprisonment. But other publicized cases, arising with disturbing frequency, suggest that this self-protective psychology operates in noncapital cases as well, and recent studies suggest that this is a widespread problem. For example, the National Registry of Exonerations (a joint project of Michigan Law School and Northwestern Law School) records that of 1,428 legally acknowledged exonerations that have occurred since 1989 involving the full range of felony charges, 151 (or, again, about 10 percent) involved false guilty pleas.
. . .
How prevalent is the phenomenon of innocent people pleading guilty? The few criminologists who have thus far investigated the phenomenon estimate that the overall rate for convicted felons as a whole is between 2 percent and 8 percent. The size of that range suggests the imperfection of the data; but let us suppose that it is even lower, say, no more than 1 percent. When you recall that, of the 2.2 million Americans in prison, over 2 million are there because of plea bargains, we are then talking about an estimated 20,000 persons, or more, who are in prison for crimes to which they pleaded guilty but did not in fact commit.
The American legal system is in serious need of comprehensive reform.