What is the test for a federal district judge to issue an injunction against the Attorney General for a violation of the Eighth Amendment?

Having identified an Eighth Amendment violation, one must then consider the propriety of the district court's remedy. "The district judge ha[s] the power only to correct the constitutional defects that he [or she] [finds]." Hoptowit, 682 F.2d at 1253; see also Toussaint v. McCarthy, 801 F.2d 1080, 1107-08 (9th Cir.1986) ("An injunction must be narrowly tailored to cure the constitutional violation and must not intrude on the functions of state officials unnecessarily."), cert. denied, 481 U.S. 1069, 107 S.Ct. 2462, 95 L.Ed.2d 871 (1987).