They have received their orders from the Sociopathic Oligarchs, one of which is the police commisioner, that he is to be convicted no matter what it takes, so they will cheat in every way possible.
It's an extremely weak case, with the video not proving anything. It doesnt show his face, that could be anyone. Every other piece of evidence could have easily been planted.
Now we know they've been listening in on his calls. This needs to be disclosed to the jury, so they see that they are so desperate to win the case that they will cheat, throwing all the other evidence, and anything they testify to, into doubt.
Luigi's trial is going to be a circus like we haven't seen since the OJ trial.