I don't think Jerry is BM. Although he is definitely sus. Maybe an inside person working for BM? 

 butterfly:

Jerry will be undercover police officer. And Tom is Big Mouse. 

I think so too and Tom is Big Mouth :D 

i have been thinking the same thing but regarding the show tom and jerry, jerry is seen as the smart one who always escapes from tom whilst provoking him. if this was a reference to the show they would have also related to the fact that tom, the cat, is always falling into jerry's trap and never being able to catch him