Does Ruiz-Alvarez have any grounds to challenge the district court's instruction of reasonable doubt?

Because Ruiz-Alvarez also failed to object to the district court's definition of reasonable doubt, we will review the instruction only for plain error. See United States v. Boone, 951 F.2d 1526, 1541 (9th Cir.1991).

Recently, in the case of United States v. Jaramillo-Suarez, 950 F.2d 1378 (9th Cir.1991), we refused to reverse after the district court instructed the jury on reasonable doubt much in the way the court instructed the jury here. Id. at 1386. After comparing the instruction in that case, see id. at 1386 n. 11, with the instruction given here, we conclude that the district court did not plainly err in its use of a disfavored instruction.