St. Louis County Executive Steve Stenger and Police Chief Jon Belmar spoke in favor of the measure at the St. Louis County Police Communications Center in west county.
Prop. P will be on the April 4 ballot.
If approved by voters, the measure would raise the St. Louis county sales tax by one half cent and generate $80 million a year.
Around $46 million would go to St Louis County Police while $34 million would be divided among the other municipal police departments in St. Louis County based on population sizes.
County police would use the funds to hire more officers, place a second police officer in patrol cars when necessary, increase salaries, put body cameras on every officer and add dashboard cameras in every police car.
“Proposition P is not only an investment, Proposition P will save lives,” Belmar said.
The county police funds would also expand officer training and help develop a computerized crime reporting system.
Critics call the measure a regressive tax and say it doesn’t guarantee more officers.
A simple majority is needed for Prop P to pass.