In 1975, prison inmates at the Pendleton Correctional Facility brought a class action, and the District Court issued an injunction, which remains in effect, to remedy violations of the Eighth Amendment regarding conditions of confinement. Congress subsequently enacted the Prison Litigation Reform Act of 1995 (PLRA), which, as relevant here, sets a standard for the entry and termination of prospective relief in civil actions challenging prison conditions. Specifically, 18 U. S. C. §3626(b)(2) provides that a defendant or intervenor may move to terminate prospective relief under an existing injunction that does not meet that standard; §3626(b)(3) provides that a court may not terminate such relief if it makes certain findings; and §3626(e)(2) dictates that a motion to terminate such relief "shall operate as a stay" of that relief beginning 30 days after the motion is filed and ending when the court rules on the motion. In 1997, petitioner prison officials (hereinafter State) filed a motion to terminate the remedial order under §3626(b). Respondent prisoners moved to enjoin the operation of the automatic stay, arguing that §3626(e)(2) violates due process and separation of powers principles. The District Court enjoined the stay, the State appealed, and the United States intervened to defend §3626(e)(2)s constitutionality. In affirming, the Seventh Circuit concluded that §3626(e)(2) precluded courts from exercising their equitable powers to enjoin the stay, but that the statute, so construed, was unconstitutional on separation of powers grounds.

Held:

1. Congress clearly intended to make operation of the PLRAs automatic stay provision mandatory, precluding courts from exercising their equitable power to enjoin the stay. The Government contends that (1) the Court should not interpret a statute as displacing courts traditional equitable authority to preserve the status quo pending resolution on the merits absent the clearest command to the contrary and (2) reading §3626(e)(2) to remove that equitable power would raise serious separation of powers questions, and therefore should be avoided under the canon of constitutional doubt. But where, as here, Congress has made its intent clear, this Court must give effect to that intent. Sinclair Refining Co. v. Atkinson, 370 U. S. 195, 215. Under §3626(e)(2), a stay is automatic once a state defendant has filed a §3626(b) motion, and the command that it "shall operate as a stay during" the specified time period indicates that it is mandatory throughout that period. The statutes plain meaning would be subverted were §3626(e)(2) interpreted merely as a burden-shifting mechanism that does not prevent courts from suspending the stay. Viewing the automatic stay provision in the context of §3626 as a whole confirms the Courts conclusion. Section 3626(e)(4) provides for an appeal from an order preventing the automatic stays operation, not from the denial of a motion to enjoin a stay. This provisions one-way nature only makes sense if the stay is required to operate during a specific time period, such that any attempt by a district court to circumvent the mandatory stay is immediately reviewable. Mandamus is not a more appropriate remedy because it is granted only in the exercise of sound discretion. Given that curbing the courts equitable discretion was a principal objective of the PLRA, it would have been odd for Congress to have left §3626(e)(2)s enforcement to that discretion. Section 3626(e)(3) also does not support the Governments view, for it only permits the stays starting point to be delayed for up to 90 days; it does not affect the stays operation once it begins. While construing §3626(e)(2) to remove courts equitable discretion raises constitutional questions, the canon of constit