Odd phone activity

So he put a fingerprint lock on his phone. Hmm. A tremendous amount of weird phone calls and times. Confronted, he says it's all over the phone bs. I don't like it obviously but I like real proof So I can say I tried everything possible before we spilt. Now he's passed out drunk. Completely wasted. I'm pregnant so I'm sober. Do you go thru the phone for positive proof? What say you all.