What is the test for establishing municipal liability for tortfeasor's actions in an action brought by a plaintiff against the municipality?

"[T]here are three ways to show a policy or custom of a municipality: (1) by showing a longstanding practice or custom which constitutes the standard operating procedure of the local government entity; (2) by showing that the decision-making official was, as a matter of state law, a final policymaking authority whose edicts or acts may fairly be said to represent official policy in the area of decision; or (3) by showing that an official with final policymaking authority either delegated that authority to, or ratified the decision of, a subordinate." Villegas, 541 F.3d at 964 (internal quotations omitted). Aside from showing an express policy or custom, "[a] plaintiff may also establish municipal liability by demonstrating that (1) the constitutional tort was the result of a 'longstanding practice or custom which constitutes the standard operating procedure of the local government entity;' (2) the tortfeasor was an official whose acts fairly represent official policy such that the challenged action constituted official policy; or (3) an official with final policy-making authority 'delegated that authority to, or ratified the decision of, a subordinate.'" Price v. Sery, 513 F.3d 962, 966 (9th Cir.2008) (citing Ulrich v. City & County of San Francisco, 308 F.3d 968, 984-85 (9th Cir.2002)); accord Villegas, 541 F.3d at 964 (Thomas, J., dissenting).