WASHINGTON » The Pentagon misled Congress with inaccurate and vague information about sexual assault cases that portrayed civilian law enforcement officials as less willing than military commanders to punish sex offenders, an Associated Press investigation found.

Local district attorneys and police forces failed to act against U.S. service members who were subsequently prosecuted in military courts for sex crimes, according to internal government records that summarized the outcomes of dozens of cases. But in a number of cases, the steps taken by civilian authorities were described incorrectly or omitted. Other case descriptions were too imprecise to be verified.

There also is nothing in the records that supports the primary reason the Pentagon told Congress about the cases in the first place: To show top military brass as hard-nosed crime fighters who insisted on taking the cases to trial.

The records were obtained through the Freedom of Information Act by the advocacy group Protect Our Defenders, which provided the documents exclusively to AP. Protect Our Defenders is scheduled to release a report today that criticizes the Pentagon’s use of the cases to undermine support for Senate legislation that would mandate a major change in the way the military handles sexual assault allegations.

The bulk of the cases involved soldiers.

Army spokeswoman Tatjana Christian said the case descriptions were written by service attorneys who had “personal and direct knowledge of the circumstances.” She said they contacted the local authorities in each case to ensure the description was accurate, although there is no indication of that in the summaries. The Army declined to make a service official available for an interview.

Previously, the more than 90 cases had been discussed publicly only as statistics that underpinned the Pentagon’s objections to the Senate bill, the Military Justice Improvement Act.

Three years ago, Navy Adm. James Winnefeld, then the vice chairman of the Joint Chiefs of Staff, used the numbers to warn a Senate panel that if approved, the bill would result in fewer sexual assault cases going to trial. Winnefeld retired from military service last year.

In response to the AP’s reporting, Joint Chiefs of Staff spokesman Richard Osial described the information that Winnefeld provided the committee as a “snapshot” based on data that was supplied by the military services.

“He had confidence to go with it,” Osial said.

The consequences could be significant if lawmakers believe they were misinformed. A backlash could stoke additional support for the Senate bill that’s failed to pass largely because of the military’s steadfast opposition. Another vote on the legislation could come as early as June.

The legislation aims to stop sexual assaults by stripping senior officers of their responsibilities to decide whether to prosecute sexual assault cases and giving that authority to seasoned military trial lawyers. Protect Our Defenders, a nonpartisan organization, supports the bill.

“Someone at the Pentagon should be held accountable,” said retired Col. Don Christensen, the organization’s president and the former chief Air Force prosecutor. “Whether you agree or disagree with the policy, every senator — especially those who repeated the claim or based their vote on the claim — should be outraged.”

The unflattering image of civilian law enforcement projected in the records also runs counter to the close working relationships local prosecutors told AP that they’ve forged with the uniformed legal staffs at military installations in their jurisdictions — far from the contentious political climate in Washington.

Civilian prosecutors said it’s not unusual to transfer a sexual assault case to the military for investigation or prosecution, particularly when the incident occurred off post and involved two or more service members. Yet these referrals are routinely depicted as refusals, leaving the impression the charges would not have been pursued had military authorities not stepped in.

“It’s offensive that they would say they would prosecute cases that we would not,” said Jaime Esparza, the district attorney for El Paso County, Texas, where the Army’s 1.1 million acre Fort Bliss is located.

At Fort Drum in upstate New York, the Army took credit for prosecuting a soldier who had been previously convicted for the possession of child pornography but was never discharged from the service. The soldier, whose identity AP could not confirm, also failed to register as a sex offender. After being allowed to stay in uniform, he groped a girl and also sent her sexually explicit messages. He then was court-martialed and sentenced to five years in prison.

Kristyna Mills, the district attorney in New York’s Jefferson County, where Fort Drum is located, disputed the Army’s conclusion that her office turned the case down. She said the decision to allow the Army to take it was a “collaborative effort” made with the legal staff at Fort Drum.

“It is extremely rare that my office ‘declines to prosecute’ a case unless there are serious evidentiary issues that we feel cannot be overcome,” Mills said.

Associated Press writer Julie Watson in San Diego contributed to this report.