The immigration law defines as an "aggravated felony" (resulting in deportation) any theft offense punished by a year or more incarceration. Today's decision confirms that this includes aiders and abettors as well as the actual thieves. The old distinctions between principals of the first and second degree and accessories before the fact are archaic and need not be considered. The Court passed on the more difficult questions about the California statute in question. It is so broad as to include accessories after the fact, which remains a viable distinction, and it includes joyriding involving such a brief deprivation of property that it wouldn't be considered theft in most states. These were not in the questions presented. The opinion by Justice Breyer was unanimous except that Justice Stevens opted out of one part, which he considered to be an unnecessary excursion into questions of California law not properly presented.