CHICAGO (CBS) – Naperville mom Karen Hanneman didn’t set out to be an activist.

But the heroin-related death of her 21-year-old son, Justin Tokar, pushed her to become one.

“Am I on a crusade? No,” she tells CBS 2’s Dana Kozlov. “But I do feel compelled to be involved.”

Hanneman is fighting for the passage of Senate Bill 1701, which would keep most people who call 911 to report an overdose — and the victim — from being charged with a crime.

“I believe that my son would have had a chance,” if such a law had been on the books, Hanneman says.

Freshman state Rep. Kelly Cassidy is fighting to get the bill passed this veto session so that other lives may be saved. 

“Drug users are together, and someone gets in trouble, there’s an overdose situation. More often than not, what happens is, friends run,” Cassidy says. “What this stops is your neighbor’s kid dying.”

Illinois would become the eighth state to pass the law. But there are immunity exceptions. Immunity would be revoked if the user dies and the person who called for help gave the victim the drugs, or if police find a large quantity of drugs at the scene. 

John Roberts is a former Chicago police captain whose son, Billy, overdosed on heroin two years ago. He’s heading to Springfield to help fight.

“Unless we erase that fear, remove that fear from their mind, we’re going to continue to see the number of fatalities go up and up,” Roberts says.

Roberts is headed to Springfield on Tuesday for day one of the veto session, in hopes of talking to as many lawmakers as he can.

The bill passed unanimously in the Senate last spring. It’s unclear, though, if Rep. Cassidy has the votes in the House or if it will come up for a vote this week.