Officer Thomas Wortham was killed back in May. A man who was out of jail on probation on gun charges is one of three suspects accused in that crime.
ABC 7's Leah Hope reports that the measure signed into law Monday was designed to keep those convicted on gun charges in jail longer.
Creating tougher gun laws is one approach to reducing gun violence. Following the recent deaths of officers Michael Bailey and Thomas Wortham, the new law is especially meaningful for some.
The location of this bill signing -- 85th and Martin Luther King -- has meaning for the Wortham family.
"Unfortunately the tragedy has befell our family has devastated us, but it has galvanized the community," Wortham said.
The new gun law was signed in Nat King Cole Park in Chicago's Chatham neighborhood. Officer Tom Wortham Jr. was president of the Cole Park Advisory Council when he was shot and killed near his parents' home in May, just across the street from the park.
With the signature of Governor Pat Quinn, the new law will requires a mandatory one-to-three-year prison sentence for aggravated unlawful use of a weapon without an Illinois firearm registration card. One of the men involved in the shooting Officer Wortham was on probation after being convicted of aggravated unlawful use of a weapon.
The signing was witnessed by politicians, activists and those directly impacted by gun violence. All in attendance agreed: more needs to be done beyond this new law.
"If you catch a young man walking with a .357 magnum, loaded, walking down the street and he gets probation, and then another probation and then another probation and another probation--that's your problem," Mayor Daley said.
"We have to go further than the legislation. We have a problem. The problem is citywide and nationwide. In order to solve the problem, it takes everyone to get involved," said Tom Wortham Sr., the father of a slain officer.
The new law takes effect January 1, 2011.
It was announced Monday a new playground will be built in Officer Wortham's name. The Cole Park Advisory Council, the park district, police department and other community organizations will create the Thomas Wortham IV memorial playground.