MADISON, Wis. -

A bill that would require independent investigations of police shootings faces an uncertain future at the Capitol.

The measure was brought about in part by friends of Paul Heenan, an unarmed man shot and killed by a Madison Police officer in November 2012.

The bill passed the state Assembly on a voice vote, and passed unanimously out of a Senate committee last week, but it isn't on the Senate's calendar for Tuesday and there's no guarantee at this point that it will be.

The state's largest law enforcement group, the Wisconsin Professional Police Association, says they're pushing for the Senate to take up the bill saying it has wide support.

"I think that this measure represents what is the most prevalent practice in the state and that's having outside agencies come in and investigate any situation that involves an officer-related death," said Jim Palmer, Executive Director of the WPPA. "This would mandate it uniformly across the board and I think there's a lot of value in that."

A poll WPPA commissioned by saint norbert college found 83 percent of 400 people polled said they had "more confidence' in the investigation of an officer's use of deadly force if the review was conducted by an outside agency. Only 10 percent thought keeping the reveiw in-house was a good idea.

The bill has also been pushed by families and friends who lost loved-ones. In Madison, following the shooting death of Paul Heenan by officer Stephen Heimsness in November 2012, Heimsness was cleared of wrongdoing by his own department and the district attorney. Michael Bell died at the hand of a Kenosha police officer in 2004 who was also cleared by his own agency.

Currently no state police agency opposes the bill, but right now it's waiting for a vote in the senate.

"If it doesn't pass we'll have to roll up our sleeves and work on it again," said Palmer. "I think everyone is eager to get to the table and have that discussion."

In a statement, Senate Majority Leader Scott Fitzgerald, R-Juneau, said the bill would not be on the calendar for this coming Tuesday but quote "still may be considered for Apri 1st." That's the last day the senate is expected to be in session, so it would have to pass that day to go to the governor's desk.