Former Minnesota State Rep. Steve Smith, who was once the longest serving Republican in the House before a 2012 primary defeat, was discovered dead Monday. He was 64.

Smith's son, Ryan Smith, told the Associated Press that the cause of his father's death is has not yet been determined, but that his father had battled alcoholism and become increasingly despondent and unresponsive to calls from family and friends.

Smith, an attorney from Mound who was first elected in 1990, chaired multiple committees before losing in the primary. Rep. Mary Liz Holberg, R-Lakeville, announced his death to the House floor Monday afternoon before a moment of silence.

Holberg said her former colleague worked tirelessly on child support issues. When reform passed, it was a big accomplishment.

"I don't think we've seen seen reform in that area to that degree since then," Holberg said.

Smith was also chief House author of the 2011 Safe Harbor for Sexually Exploited Youth Act, an innovative law geared toward ending child sex trafficking. The bill changed state law to treat sex-trafficked children under 16 as crime victims, not criminals who could be sentenced to juvenile detention.

The law also required the state departments of Public Safety, Human Services and Health to work with experts to create a prevention and support model for victims.