“Because of the death, though, the police have to treat the case as a homicide. “
eh? The police have to collect evidence and fill out the paperwork. In cases like this they don’t decide what charges to bring, the State Attorneys office does.
I agree. That's exactly what I was referring to as "treat the case as a homicide". Collect any evidence, prepare their report, and turn it over to the DA. The police would do that regardless of whether or not the prosecutor later decides to press charges. I never said that the police decided on the charges.