Steven Musil/CNET

The Federal Trade Commission is reportedly investigating TripAdvisor after the travel recommendation site was accused of censoring users' reports of rape and assault in reviews of resorts on the site.

The investigation was revealed in a letter sent last week to Sen. Tammy Baldwin, a Wisconsin Democrat, by the FTC, the Milwaukee Journal Sentinel reported Tuesday.

"The commission has a strong interest in protecting consumer confidence in the online marketplace, including the robust online market for hotel and travel," Maureen Ohlhausen, acting chairwoman of the FTC, wrote to Baldwin.

"When consumers are unable to post honest reviews about a business, it can harm other consumers whose abilities to make well-informed purchase decisions are hindered and harm businesses that work hard to earn positive reviews."

The agency's probe is apparently in response to an investigation conducted by the Journal Sentinel that found that the site deleted reports of rapes, blackouts and other injuries and deaths among travelers vacationing in Mexico.

A week after the Journal Sentinel's report was published earlier this month, TripAdvisor started adding warnings to business pages where public safety issues -- including sexual assault -- have been reported. The badges will remain on a company's page for three months, but will be extended for longer if reports persist.

TripAdvisor said it was unaware of an FTC investigation and hadn't been contacted by the agency.

"As a user-generated content platform that receives hundreds pieces of content per minute every day, we believe our guidelines work well, but we also know we don't always get it right," the company said in a statement. "As we always do, we continue to review our guidelines and will continue to update them to better serve our users and businesses we support."

The FTC declined to comment specifically on TripAdvisor, citing agency policy of not confirming the existence of investigations. The agency did say, however, that a site making false statements about its services may violate federal law.

"Claims that a user review website makes about its services may violate the FTC Act if they are false or misleading," the FTC said in a statement. "Whether taking down negative reviews violates the FTC Act would depend on the particular facts."

First published Nov. 21 at 5:44 p.m. PT.

Updated Nov. 22, 8:40 a.m. PT: Adds comment from the FTC.

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