Can I evict a tenant for allowing unauthorized occupants to live in the property?

You may evict a tenant who has a lease agreement only if they have materially breached a term of the lease agreement. Many leases have provisions stating that only the parties to the lease will live in the property. If your lease has this type of provision, you may be able to evict a tenant for allowing additional occupants to live in your rental property. 

It is worth noting that at least one Texas court has found that a tenant having their significant other move into the leased premises was not a material breach of the lease, and the landlord lost the eviction case.