The Navy is reporting surprising success in a program to get sailors at Naval Station Great Lakes, near Chicago, to stop raping their comrades. Sexual assaults have been epidemic at the station, where about 40,000 recruits complete boot camp each year. But crimes at the station’s Training Support Center, where about 16,000 sailors receive specialized training, and where most of the assaults occur, have fallen about 60 percent over two years.

The program includes counseling, videos and “town patrols” of bars and clubs. Recruits are taught to intervene when friends behave badly. The Navy says it has no idea why this is working, but apparently it is.

It’s hard to complain about any reduction in sexual predation. But it is also fair to note that Great Lakes is an anomaly in the midst of a crisis. A Pentagon survey in May found that assaults across the armed forces rose sharply last year, to 26,000 in 2012, compared with 19,000 in 2010. And while those figures, rough estimates derived from confidential surveys, are appalling, even more so are these: only 3,374 incidents were actually reported in 2012, and a mere 302 were prosecuted.

It’s fine that one base is tilting in the direction of “zero tolerance.” And good for the Navy for expanding the program to San Diego and some bases in Japan.