Legal Question in Criminal Law in Tennessee

The situation is very "fact specific," meaning the physical layout of the house is important, the locks/keys on the door are important, and whether or not the owner/landlord has the right to freely enter the tenants private area, is important.

The general answer is no, a landlord cannot speak for a tenant and give the police permission to search the tenants private area (the area where the tenant has a "reasonable expectation of privacy"). BUT, if the tenant has no lock on the door, leaves the door open, allows the landlord to come and go in the room and allow guests to come into the room (for example, to use the bathroom, while the tenant is away) then a court might rule that the tenant had no reasonable expectation of privacy, at least for items not otherwise locked up or secured.