I'm looking for a movie title!

Hello everyone.

I'm looking for a French movie that I saw a long time ago (over 30 years ago) in the 80s/90s.

It seems to be a police thriller with these elements that I remember:

A picnic that ends in an erotic scene (I believe it's a story about infidelity).

An actor has his ear cut off after a quarrel among friends, they put the ear in a champagne bucket with ice cubes and take it to the hospital.

Police officers come to arrest a disabled man who has canes with lights, he has booby-trapped them with dynamite and blows them up.

So, if anyone has the name of this film or TV movie, it would be great if I could find it.

Thank you all.