The department has no jurisdiction over the officer. Without analyzing the merits, a police officer can be sued after retiring

Please see my comment in mu colleague's answer

There are other procedures including motions to suppress and motions to exclude or in limine

He faces life imprisonment. . .

It means second degree murder with a depraved mind without premeditation. You can google to get a comprehensive explanation

The person with the most knowledge is her attorney who she should speak with

This is not something which should be discussed in a public forum. He needs the advice of an attorney directly and not through his parent.

And the question is? Discuss this with your criminal defense attorney

Switched to personal injury It is not civil rights because it was not done by government

If you feel you are not properly represented, then retain private counsel