Gunman in Colorado supermarket shooting is the latest to fail with insanity defense

A man who killed 10 people at a Colorado supermarket has been found guilty of murder in the 2021 attack, becoming the latest person to fail in an attempt to be acquitted by reason of insanity.

Jurors found Ahmad Alissa guilty on Monday. As a result, instead of remaining in a state hospital for psychiatric treatment, he was sentenced to life in prison.

Suspects who claim insanity don't usually succeed before juries in the U.S. Other examples include James Holmes, who killed 12 people at a Denver-area movie theater in 2012 and is serving life in prison.

It has become harder to succeed with an insanity defense since a federal jury found John Hinckley Jr. not guilty by reason of insanity for shooting President Ronald Reagan in 1981. The verdict stoked public skepticism about insanity pleas, leading to tougher federal and state requirements to reach acquittals, according to Christopher Slobogin, professor of law and psychiatry at Vanderbilt University.