Metropolitan Police Department Chief Cathy Lanier (R) at a press conference at Washington police headquarters on January 3. Lanier says she can’t verify a claim that sexual assault reports are missing but encourages victims to come forward. (Robert MacPherson/AFP/Getty Images)

D.C. police will create a Web site where sexual assault victims who think their complaints were mishandled can file a grievance, an initiative stemming from a watchdog group’s allegations that the department failed to document 170 reported sex assaults during a three-year period.

Police Chief Cathy L. Lanier said grievances filed through the site will get a fresh look from detectives to ensure that cases were handled properly. Lanier also is ordering two detectives to review all sexual assault complaints filed from 2008 through 2011 that were classified as “office information” or “miscellaneous” — terms Human Rights Watch says are an indication that reports were shelved and not properly investigated. The police department has stopped using those terms when filing reports involving sexual offenses.

The initiatives are part of the police department’s response to a 197-page Human Rights Watch report that is scheduled for release Thursday. The New York-based rights organization spent 22 months examining whether authorities failed to properly document allegations of sexual assault and rape, according to the group. In some cases, Human Rights Watch alleges that officers disparaged victims and intimidated them into not following through with cases, according to a letter the report’s author sent to D.C. police in December.

In advance of the report’s release, Lanier and Assistant Chief Peter Newsham have asked the Justice Department to review the department’s files.

On Sunday, D.C. police posted a link to the Human Rights Watch report on the department’s Web site; the link opens the embargoed version of the report that was given to some media outlets, including The Washington Post. The Post is honoring the Thursday embargo, and a Human Rights Watch spokeswoman on Sunday declined to ease the restriction or comment for this story.

Police also were given early access to the report, and Lanier said she is not beholden to the media embargo. D.C. police previously released some of the report’s details and conclusions.

District authorities and Human Rights Watch have sparred for months over access and the public release of internal correspondence from both sides, differing on methods, statistics and conclusions. The rights group says it has uncovered systemic problems of police misconduct. Newsham says the author provided anecdotal stories from a handful of unnamed victims — about 15 out of 1,500 complaints — and repeated the uncorroborated statements “over and over again to say the problem is greater than it actually is.”

Lanier said she is worried that the report will scare women and discourage them from reporting sexual assaults. “As a woman, not to mention the police chief, I am afraid that the Human Rights Watch report will do the opposite of what they intend,” she said over the weekend.

The chief has made it a top priority to combat sexual assaults, particularly attacks involving acquaintances, which she says are growing more frequent and are among the most difficult cases to solve. Lanier said victims often don’t want to cooperate or were too intoxicated to know what happened to them.

Lanier has been teaching bar owners how to spot potential trouble and has put up hundreds of warning posters in restrooms.

“All of our hard work could be undermined,” the chief said, referring to the report. Lanier said the number of reported sexual assaults in the District increased last year by 51 percent compared with 2011, something she says is due in part to efforts to encourage victims to come forward.

Human Rights Watch counters that it performed an exhaustive investigation of documents from four city agencies and fought for access to information through the courts. The report contains accounts from women who say they weren’t taken seriously or had no reports taken at all, according to letters the group sent to the police department.

Lanier and Newsham said the department used to classify complaints of all types “office information” and “miscellaneous,” typically when detectives could not determine whether a crime had occurred. Those reports are filed in an intelligence database, and in such cases there would not be a public police report. Newsham said the complaints are still investigated and could be reclassified as crimes as detectives gather more information.

Lanier said police are no longer classifying sexual assault cases in that way. Instead, she said, each allegation involving improper sexual conduct will now be written up in an official offense report. Also, new crime-tracking software will allow police to give multiple classifications to some crimes, such as when a woman is sexually assaulted during a burglary.

One of the most substantive and troubling problems Human Rights Watch told the police it uncovered was the missing 170 sexual assault reports. The group told the department it found 480 complaints between October 2008 and September 2011 in which a woman reportedly asked for a police investigation and underwent a forensic exam at MedStar Washington Hospital Center, the only hospital that performs the test in the District.

The rights group wrote in letters to the police department that it tried to match police reports to those 480 cases but could not find corresponding documents for 170 cases. The groups told police a more exhaustive search of the police department’s intelligence files, which includes the cases not written up in offense reports, did not reveal cases matching the hospital documents in 170 complaints.

Newsham, the assistant police chief, said the rights group has not given police enough information to determine whether reports are missing. He said police found 360 hospital reports, not 480, and have found corresponding police documents for each, either in the form of public crime reports or in the intelligence database.

The group told police that because police are required to file reports within a day of the complaint, investigators tried to find police reports filed within 24 hours of a hospital report, Lanier said. If no report was found, the group deemed such reports missing, she said.

Lanier called such methodology flawed and the conclusions based on assumptions. She said it can take several days for reports to work their way through the system, so the group could have missed many. Lanier said victims sometimes tell hospital nurses that they’ve notified police even if they haven’t, and so relying on that information from hospital reports alone can be misleading.

Newsham said the new police Web site could help victims who think their cases weren’t investigated to come forward. In addition, Newsham said detectives are going back to the hospital and reviewing cases in which forensic exams were completed to “ensure that a police report or [intelligence records] were completed for each case.”