Chicago will reform its police to reduce use of force. Here’s why it might not work.

Chicago Mayor Rahm Emanuel announced on Wednesday that the city will focus on reforming police policies to reduce excessive use of force incidents, following protests over the police shooting of Laquan McDonald and the Justice Department’s announcement that it will investigate the Chicago Police Department.

According to the Associated Press, Emanuel said the city will change police training and department polices on use of force, borrowing ideas from other departments across the country, including Cincinnati and New York. He will also equip police officers with more Tasers — the police department will double its stock of stun guns from 700 to 1,400, with a goal to eventually equip every patrol car with one.

“Our police officers have a very difficult and dangerous job. They put their lives on the line so the rest of us can be safe,” Emanuel said. “And like all of us, they are human and they make mistakes. Our job is to reduce the chances of mistakes.”

But will it restore trust in police? It’s hard to say. As I’ve written before, the problem with police shootings is twofold: On one hand, the law and department policies only require that an officer reasonably perceive a threat, as judged by a judge, prosecutor, and jury. So cops are given a lot of legal leeway to use force even when it might not be totally necessary.

On the other hand, study after study suggests that police are more likely to see a threat in a suspect who’s black. So a cop is likely to disproportionately use that legal leeway against black suspects over white ones. The result is that even though the lax rules on police use of force appear to be race-neutral, they may in fact let cops get away with subconscious — or overt — racial biases.

Legal, policy, and training reforms can, in theory, address both of these issues, by raising the standard for use of force and training officers to resist potential racial biases. The changes in Chicago may address both, but it’s unclear how far they’ll go.

Whether reforms will actually succeed in reducing excessive use of force — and, as a result, restore public trust — depends a lot on the implementation. After all, in the case of Freddie Gray, who suffered a fatal spinal cord injury while in police custody, the Baltimore police officer who already went to trial explicitly argued that he did not act unreasonably when he neglected his city’s police policies and allowed Gray to die without medical help because it’s standard for cops to ignore some department guidelines. So it’s one thing to have rules on the books, but it’s another thing to actually enforce them.

Given that Emanuel and the Chicago Police Department already face a lot of distrust, the public will likely remain very cautious of any reforms until they are actually implemented and the city somehow demonstrates that it’s serious about reducing deadly use of force incidents. A plan may win back some public confidence, but in the end it will only be as good as its implementation.