DENVER (AP) — Colorado lawmakers are considering whether to make it tougher for defendants to be found not guilty by reason of insanity, prompted in part by last summer's mass killings at a movie theater.

A bill up for debate in a legislative committee next week would require defense lawyers to prove a defendant is insane by clear and convincing evidence. The current standard requires prosecutors to prove defendants are sane.

Two high-profile Colorado cases thrust the issue into the spotlight.

Lawyers for James Holmes, charged with killing 12 in the theater shootings, say he's mentally ill. Some expect Holmes to enter an insanity plea.

In 2010, a man charged with wounding two students outside a Denver-area school was found not guilty by reason of insanity. He was committed to a mental hospital.