CAAFLog blogged a while back about the declining numbers in Courts-Martials held. Navy Times reports this as a possible explanation for lower Navy numbers:
The overall number of sailors facing courts-martial has dropped dramatically during the past several years, Navy records show.
General courts-martial for the most serious offenses have fallen by nearly half, from 172 in 2005 to 94 last year. Court cases for lesser crimes have fallen by even more, according to data provided by the Navy’s judge advocate general.
The Navy’s top lawyer said the decline is across the board and not caused by a large drop in any particular type of prosecution. A key reason may be that sailors are spending more time at work and on deployment than in past years