Sex Crime Wave Involving East Asians and American Indians?

I blogged about this back in 2002, but I thought I'd mention it again; it's one of my favorite simple statistics puzzles. The federal Sentencing Commission provides a table breaking down all sentenced federal offenders, broken down by offense type and race. The race categories are White, Black, Hispanic, and Other. (I realize that demographers generally view Hispanic as an ethnicity, not a race, but the Commission follows the more common lay usage here.)

For sexual assault, 51.3% of all offenders are "other." Among the U.S. public as a whole, probably only about 6% would fall into the "other" category (subject to some uncertainty that's not relevant here, since any estimate would be far below 51.3%). What's up? I'll post the answer to the comments in a few days, if no-one else gets it before then (though I suspect they will).