Democratic presidential candidate Julián Castro released a plan on Monday morning to overhaul policing in the United States, with an eye on preventing the police shootings of unarmed people of color that have prompted national outrage in recent years. 

In the third policy proposal of his campaign, the former U.S. housing secretary and San Antonio mayor outlined his plan to end “overaggressive” policing that disproportionately targets raicial minorities. Castro previewed the plan Saturday in San Francisco while appearing at the MoveOn Big Ideas Forum. Echoing an argument he has made since launching his campaign, Castro questioned why Dylann Roof, a white supremacist who killed nine people in the 2015 Charleston church shooting, can be arrested without incident but people like Stephon Clark cannot. Last year, Sacramento police shot and killed Clark, a young black man, while responding to a vandalism complaint. 

“How many of these videos do we have to watch to understand that even though we have some great police officers, this is not a case of bad apples?” Castro said.

Castro’s proposal would set up national standards for police departments that receive federal funding and limit the use of deadly force to when “there is an imminent threat to the life of another person, and all other reasonable alternatives have been exhausted.” To hold police accountable, Castro would create a public national database of officers who have been decertified and collect better data on police stops, bolstering existing reporting programs. Castro plans to “demilitarize the police” by issuing an executive order that prevents them from obtaining items including high-caliber rifles.

Like his immigration plan, Castro’s policing overhaul makes him the first 2020 contender to address the issue with a detailed platform.