You're completely frustrated with your tenant and you want to lock this person out. Maybe they're destructive to the property, create a racket at night and upset other tenants, or have ignored notices about late rent payments. Don't make any hasty moves. States and municipal jurisdictions have detailed procedures about how to legally evict tenants, and forcing them out by changing locks is often unacceptable.
Legal Consequences of Locking Tenants Out
Changing the locks on tenants without following legal procedure is one type of strategy known as a self-help eviction. Most states prohibit self-help evictions. Your state might allow this action in certain circumstances, but you would probably have needed to address this in the lease.
For instance, your state may allow you to change the locks if the lease has a provision about this potential action. For example, the provision would alert tenants that being delinquent on rent could lead to a lockout after a written notice.
If a lockout isn't legal in your state, you may have to pay a fine. You might have to reimburse the person's living expenses while they couldn't get into the residence. You will most likely have to let them back in. Under many circumstances, the tenant will legally be able to continue living there. After all that aggravation, you still need to pursue the legal eviction process or wait for the lease to run out.
You also run the risk of retaliation by an angry renter if you take that sort of bold step. You might find a good bit of damage inside the residence and have no way to recoup the cost for repairs aside from keeping the security deposit.
What to Do Now
Call the general number at your courthouse and ask to speak to someone about starting the eviction process. You'll need to file a notice in court, but if you've never done this before, you'll want someone to walk you through all the steps.
After the tenant voluntarily moves out or the eviction process progresses to a certain point, that's the time to call a locksmith from The Lock Shop and get the locks changed. Your state might allow this action within a certain time frame if the tenant has been served a legal notice of eviction by the sheriff's department. You'll want to deal with the locks as soon as it's legal to do so, even if the tenant has returned the keys, since they could have made copies.