Q My mother-in-law moved into a new apartment in the building she'd been living in -- pest-free -- for several years. After she moved in, we discovered bedbugs in the new unit. The manager brought in a pest control company, which recommended a heat treatment, then presented my 88-year-old mother-in-law with an invoice for more than $2,000.

My wife and I cleaned the apartment thoroughly. We removed all infected material, vacuumed everything and sprayed the unit with a recommended spray. Still, the manager taped a letter to her door threatening to sue her if she doesn't agree to pay for the treatment.

We don't want the heat treatment because we're worried about what it will do to the furnishings. We want them to treat with conventional methods -- and to pay for the treatment. How should we proceed?

A There is no relevant Minnesota statute that specifically covers bedbugs, so your mother-in-law's situation falls under the general statute, Minn. Stat. 504B.161(2). Ordinarily, landlords are responsible for maintaining the premises, except when the disrepair has been caused by the willful, malicious or irresponsible conduct of the tenant or their friends.

If a tenant moves in and bedbugs are later discovered, a landlord probably has a good argument that the tenant was responsible for bringing them into the apartment. However, a longtime tenant such as your mother-in-law has a good argument that the bugs migrated from another unit in the building and that she is not responsible.

Current literature holds that bedbugs often are picked up while traveling and that many hotels have infestations. If your mother-in-law has not traveled anywhere recently, then she can probably assert with confidence that the bedbugs are the landlord's responsibility.

That said, your mother-in-law may not be successful in contesting the charge for the treatment. If she doesn't pay, the landlord can start an eviction, and your mother-in-law will have to win that case in order to keep living in the unit. If the landlord simply sues your mother-in-law, then she doesn't have to worry about losing her unit, so long as she can pay any judgment the landlord receives if she were to lose.

If the landlord does agree to pay for the pest control, he may be able to insist on the heat treatment because a court may find that reasonable.

Your best bet is to talk with a housing advocate. Minnesota Home Line, a nonprofit tenant advocacy organization (612-728-5767, www.homeline.org), will give you advice and may help your mother-in-law negotiate a resolution with her landlord.

Kelly Klein is a Minneapolis attorney. Participation in this column does not create an attorney/client relationship with Klein. Do not rely on advice in this column for legal opinions. Consult an attorney regarding your particular issues. E-mail renting questions to kklein@kleinpa.com, or write to Kelly Klein c/o Star Tribune, 425 Portland Av. S., Minneapolis, MN 55488. Information provided by readers is not confidential.