Is intoxication a valid defense to the mens rea of specific intent?

"The defense of intoxication, even if that intoxication was voluntary, [is] a valid defense to the mens rea of specific intent." United States v. Martinez-Martinez, 369 F.3d 1076, 1083 (9th Cir. 2004). Where "an accused has offered evidence to raise the issue, his

Page 11

capacity to form specific intent at the time of the offense becomes an element which, like all other elements of the crime, must be proved by the government beyond a reasonable doubt." United States v. Echeverry, 759 F.2d 1451, 1454 (9th Cir. 1985). However, "proof of intoxication, in and of itself, does not excuse commission of a specific intent crime." Id. at 1455.