By Larry Shaughnessy

No other crime, not even drugs, leads to more court cases in the U.S. Navy than sex offenses, according to an internal report out this week.

The Navy reported there had been 135 courts-martial involving sailors around the world in the first six months of 2013 and about 36% involved a sex-related charge.

The report covers charges like adultery or attempted indecent acts up to sex assault and rape.

The report was conducted at the insistence of Navy Secretary Ray Mabus.

"This department is fully committed to using all available resources to prevent this crime, aggressively investigate allegations and prosecute as appropriate. We will not hide from this challenge. We will be active, open and transparent," Mabus said.

The report comes amid mounting concern about sex abuse reports in the armed forces.

Recent figures show an increased rate of reported assaults. Recent high-profile cases have involved officers in the Air Force and the Army. The U.S. Naval Academy is also faced with a sex assault case involving football players.

President Barack Obama and military leaders have vowed change. Legislation in the Senate would remove sexual assault cases from the military chain of command. A recent report from a government watchdog found that in many cases the military did not properly investigate sexual assault claims.

But not every Navy courts-martial resulted in a conviction. Of the 14 cases of sex assault prosecuted by the Navy during the period in the report, 10 resulted in not guilty verdicts.