The Pentagon is coming under pressure to give Congress detailed information on the handling of sex-crime cases in the armed forces following an Associated Press investigation that found a pattern of inconsistent judgments and light penalties for sexual assaults at U.S. bases in Japan.

Democratic Sen. Kirsten Gillibrand of New York, who's led efforts in Congress to address military sexual crimes, is pressing the Defense Department to turn over case information from four major U.S. bases: Fort Hood in Texas, Naval Station Norfolk in Virginia, the Marine Corps' Camp Pendleton in California, and Wright-Patterson Air Force Base in Ohio.

Such records would shed more light on how military commanders make decisions about courts-martial and punishments in sexual assault cases and whether the inconsistent judgments seen in Japan are more widespread.

AP's investigation, which was based on hundreds of internal military documents it first began requesting in 2009, found that what appeared to be strong cases were often reduced to lesser charges. Suspects were unlikely to serve time even when military authorities agreed a crime had been committed. In two rape cases, commanders overruled recommendations to court-martial and dropped the charges instead.