That would be voluntary manslaughter, I don't think that police officers have traditional way to kill with malice. Please, understand them, their jobs are very dangerous. Although some police officers get convicted with murder though, when it is in reality voluntary manslaughter.
I wanted to say one thing, even illegal drugs can cause Bipolar Disorder, you should still get medical attention and then get punished for doing illegal drugs, but that is when you recovered.
That is why there is trust issues between some people with Bipolar and Related Disorders and law enforcement agencies.