I called the police on my teacher for giving me a D on my test
Why would you do something like that for something so minuscule? Are you seriously serious?
There are many reasons. I talked to my teacher first today, but he says it's too late to change the grade.
Calling the police on you teacher for him giving you a D on your test is wrong and extremely wasteful. If you're upset about your grade that you got you should had asked your teacher to see what you could've done the do better on the test. Continuing to waste the police time could wind up in your parents getting in trouble.
I'm going to do this, my teacher is scum compared to what the police can do to me or my parents.
The police have nothing to do with this issue. You have to resolve it between the school, teacher and yourself. Why not just get to studying more, teachers don't give bad grades for no reason.