Bowman said such sites might be "helpful to look at, but you need to take everything with a grain of salt."
"Certainly all of this gives me pause, whenever there's information out there that's being kept on people that they don't know about," Bowman said. On the other hand, "there are many, many, many kinds of these things out there. I don't know that this is any better or any worse."
She pointed out that the network relies on people submitting information.
"All of that is based on the credibility of the people posting," she said.
Prospective tenants turned down for a rental should ask why, she advised.
Cornish, of Baltimore Neighborhoods, said tenants have more recourse when landlords take a dispute to court. "Those things are easier to go back and straighten out," she said.
She's heard of landlords refusing to offer a reference to tenants in an attempt to keep them from moving. The ACLU's Stanley said that landlords have a First Amendment right to write about their experiences on the Internet, but companies that act as commercial databases - as well as commercial data aggregators - should be subject to the privacy laws that credit companies face.
Landlords also have other options to inform their peers about potentially difficult tenants. They can pay to inform credit reporting agencies of outstanding debts, such as unpaid rent, said Joseph Rooney, deputy commissioner for financial regulation for the Maryland Department of Labor, Licensing and Regulation.
"If landlords would use the credit reporting system to report negatives, there's a legal framework where people can dispute the amount owed," Rooney said.
For example, if you are denied credit based on negative information on your credit report, you can get a free copy to verify the information and challenge potential inaccuracies.
Legal filings, including judgments and liens, should also appear on a person's credit report, Rooney said.
liz.kay@baltsun.com
Renters need safeguards, too
Renters can take several precautions to protect themselves when looking for a new apartment.
Check your credit report regularly. Make sure that there are no errors, such as eviction judgments, listed that would discourage a landlord from renting to you.
If turned down for a rental, ask why. A potential landlord is not required to answer, but he or she might give you a clue about why you were turned down.
Know your rights. Each county and Baltimore City have their own rules about landlord-tenant interactions.
The consumer protection division of the state attorney general office offers a brochure with more information for landlords and tenants, available online at www.oag.state.md.us/consumer/landlords.htm. Paper copies can be requested by calling 410-576-6500 or 888-743-0023.