SAN DIEGO — An investigating officer has recommended dismissing murder charges against a Marine accused in the slayings of three Iraqi men in a squad action that killed 24 civilians in Haditha, according to a report released Tuesday.

The government’s theory that Lance Coporal Justin L. Sharratt had executed the three men was “incredible” and relied on contradictory statements by Iraqis, Lieutenant Colonel Paul Ware said in the report, released by Mr. Sharratt’s defense attorneys.

“To believe the government version of facts is to disregard clear and convincing evidence to the contrary, and sets a dangerous precedent that, in my opinion, may encourage others to bear false witness against Marines as a tactic to erode public support of the Marine Corps and mission in Iraq,” Mr. Ware wrote.

Defense attorneys James Culp and Gary Myers said in a statement that he was pleased with the report and that it “reflected the value of the calm of a courtroom and the adversarial process.”

Mr. Sharratt’s mother Theresa said she was overjoyed.

“This is a huge result, that report is a declaration of Justin’s innocence,” she said. “This is very, very good news.”

The recommendation is nonbinding. A final decision about whether Mr. Sharratt should stand trial will be made by the commanding general overseeing the case Lieutenant General James Mattis.

It is the second time an investigating officer has recommended charges not continue to trial in the killings. In the case of Marine lawyer Captain Randy W. Stone, the investigating officer recommended his dereliction of duty charge be dealt with administratively.

Three enlisted men are charged with murder and four officers are accused of failing to investigate the killings. On Nov. 19, 2005, a roadside bomb blast killed one Marine and in the aftermath other members of his squad killed two dozen Iraqis, including women and children in their homes.

Prosecutors at Mr. Sharratt’s preliminary hearing introduced several accounts from Iraqis that said Mr. Sharratt had separated four men from a group of women and children and ordered them into a house. There, in a bedroom, he shot three of them and when he ran out of bullets the squad leader Staff Sergeant Frank Wuterich allegedly shot the fourth.

Mr. Sharratt’s case is the first of the three men who are charged with murder to go to a hearing known as an Article 32 investigation, the military equivalent of a grand jury.