In what circumstances will the district court dismiss an action for failure to state a claim?

We review de novo the district court's dismissal of an action for failure to state a claim. Buckey v. County of Los Angeles, 968 F.2d 791, 793-94 (9th Cir.), cert. denied, 113 S.Ct. 599 (1992). We accept all allegations of material fact as true and construe the complaint "in the light most favorable to the nonmoving party." Id. at 794. A complaint should not be dismissed under Rule 12(b)(6) "unless it appears beyond doubt that plaintiff can prove no set of facts in support of [his] claim which would entitle [him] to relief." Id. (quotation omitted). Although we construe pro se civil rights complaints liberally, a pro se litigant must supply the essential elements of the claim. Id.