... legislation that penalizes officers on duty for the murder of unarmed and restrained citizens similarly to the penalty of first-degree murder

We assume this means the murder of an unarmed at the hands of a police officer. But it doesn't say that. It just says "murder of unarmed", without saying who commits it.

So, police are called into a domestic disute. They try controlling the two sides. One side gets mad about the police presence and shoots a bystander. The officer is tried for murder because their presence caused someone to shoot someone else.

Any lawyers here want to dispute that?