Of course it’s legal to interview tenants in the States, a landlord should simply avoid violating the Fair Housing Act in a particularly flagrant manner while doing so. (E.g., they should avoid documenting in writing that they’re refusing to rent on the basis of familial status! This parenthesis possibly based on a true story.)

Give it another couple years and I’m sure the courts will dismantle the FHA. Then landlords will have to find something else to complain about.