The chairman of the D.C. Council’s public safety committee said Friday the city will enlist a law firm to examine allegations that District police failed to document and investigate at least 170 sexual assaults.

The move is the most significant effort yet to examine a 197-page report and the police department’s strong denials stemming from an investigation by Human Rights Watch, which released its findings Jan. 24.

Both the rights group and D.C. Police Chief Cathy L. Lanier have asked the U.S. Department of Justice to conduct an independent investigation. A City Council hearing has been promised.

Tommy Wells (D-Ward 6), who recently took over the committee overseeing the police department, said a firm with former prosecutors and public defenders will investigate.

“What I want is a fair, independent assessment of the report and then an assessment of MPD’s rebuttal, and I want an independent organization to work with me and figure out what should be done,” he said.

The New York-based rights group criticized D.C. police’s handling of rape and sexual assault cases over a three-year period, roughly from 2008 through 2011, and alleged numerous problems.

Author and investigator Sara Darehshori said her staff could not match at least 170 complaints of sexual abuse given to nurses at a hospital rape center with police reports filed with the city. Other sexual assault reports, Darehshori said, were filed as “miscellaneous” or as “office report” and shelved without being properly investigated.

The report also interviewed at least a dozen women who said they felt intimidated by police officers who talked them out of filing complaints, thus ending investigations and keeping attacks out of the statistics.

Lanier has vehemently denied the allegations and publicly criticized the report, saying the author purposely used skewed data to fit a preconceived agenda. In a statement after the report’s release, the chief said the authors made “sweeping allegations that are not backed by facts and undermine the credibility” of Human Rights Watch. She also outlined reforms to address some allegations she found substantive, such as no longer classifying some sexual assault reports as “miscellaneous.”

Lanier said in an email that she had no idea about Wells’s plan. “I was a bit shocked he didn’t let me know but I welcome the idea. I have some additional information I will be releasing soon as well.”

Wells would not identify the law firm to be hired.