Defense Secretary Robert Gates has launched an investigation into who leaked a Pentagon study on the effects of ending “Don't Ask, Don't Tell,” the 1993 law that bans gay and bisexual troops from serving openly.

Citing two unidentified sources familiar with the report, the Washington Post published details of the study's findings on Thursday, nearly three weeks before its planned release.

“The secretary strongly condemns the unauthorized release of information related to this report and has directed an investigation to establish who communicated with the Washington Post or any other news organization without authorization and in violation of Department policy and his specific instructions,” Pentagon Press Secretary Geoff Morrell said in a statement on Friday.

Morrell added that Gates “is very concerned and extremely disappointed that unnamed sources within the Department of Defense have selectively revealed aspects of the draft findings” of the report.

The Post reported that the report will show that most troops are not concerned about serving and living alongside openly gay troops. More than 70 percent of respondents to a questionnaire sent to more than 40,000 active-duty and reserve troops over the summer said the effect of lifting the gay ban would be positive, mixed or nonexistent. Forty percent of Marines objected to the change, the highest rate among the armed forces.

Congress is debating whether to attempt a second effort at repealing the law over the lame-duck session that begins Monday, and Morrell suggested the leak was designed to ease the objections of some lawmakers.

The leak was designed “presumably to shape perceptions of the report prior to its release,” he said.