DENVER -- Colorado is debating a proposal to encourage drug users to report overdoses. A bill giving limited criminal immunity to people who report overdoses faces another test Thursday in the Colorado Legislature.

Illinois and Washington state already have so-called "911 Good Samaritan" laws giving limited immunity to overdose reporters. Advocates say drug users sometimes don't report overdosing friends because they're afraid of facing legal trouble themselves.

Colorado's measure would require overdose reporters to remain at the scene of the event until law enforcement or emergency medical personnel arrive. They would also have to identify themselves and cooperate with authorities.

The bill has already passed the Senate. It faces a hearing in the House Thursday.