Is a waiver of a statutory right enforceable?

voluntary waiver of a statutory right is enforceable. [Citation.] For this reason a prisoner may not collaterally attack a judgment if the prisoner waived the right to do so." United States v. Racich, 35 F.Supp.2d 1206, 1210 (S.D. Cal. 1999). However, a waiver cannot bar a claim that relates to the validity of the waiver itself. United States v. Abarca, 985 F.2d 1012, 1014 (9 Cir. 1993). Since, as noted, a knowing and voluntary waiver of a right is valid, the challenge to the validity of a waiver is typically based on the allegation that the defendant's attorney was ineffective in carrying out the essential duty of fully informing the defendant of the nature and consequences of the plea and, in particular, of the nature of the rights being waived.