Impersonating police officers is a crime.
sorry fun police
I honestly don't think what Destroyer did would really be seen as a crime in the eyes of anyone smarter than a tree. I mean, all he did was have lights and happen to have a car looking similar enough to an undercover cop car. Similar enough to scare a few little kids throwing rocks at buildings' windows.
Now, when it comes to doing it to pull people over and diverting traffic for themselves, sure, it's not right.
EDIT:
now I'm reading the title as"some friend made me cake on my birthday" somehow
What..?