Unsigned Roommate's Time is Up

My question involves a roommate in the State of: Utah, Salt Lake City

Hi, My boyfriend has a roommate that is living with him unsigned and is not keeping up his part of the apartment(dirty dishes, trash, etc) He has destroyed property also. My boyfriend gave him verbal notice 2 weeks ago and written notice 2 days ago and he has made no attempt to move out. Are we allowed to give him another 24 hours grace period and then remove his belongings and hope the police will not need to be involved?

Any advice to know what our rights are would be helpful ASAP.

No, you're not.

If this is your boyfriend's subtenant, he needs to follow the law and evict him. If he's a roommate, not a subtenant, your boyfriend's landlord would have to evict him.