Yes. It happened most recently in Nebraska, where 6 men were sentenced to various prison terms for involvement in a murder they had nothing to do with, because some of them “confessed” after being threatened with the death penalty. DNA tests have ultimately exonerated them all, revealing that, according to the Lincoln Journal Star, the state’s case was a “complete fiction” and “entirely fabricated.”
The death penalty is often touted by prosecutors as a useful tool for convincing suspects to confess or to plead guilty. Here, it is clear that the results can just as easily be false confessions or erroneous guilty pleas. As with torture, the information obtained by this approach is just not reliable.
Threatening someone with the death penalty is no more a useful tool for eliciting an accurate confession than torture, and it is just as odious, immoral and flagrant a violation of human rights. And the fact that some investigators still believe they can rely on it is all the more reason to abolish it once and for all.