Opinion for the Court filed by Circuit Judge GARLAND.
This case represents the first time in more than twenty years 1 that the Federal Mine Safety and Health Review Commis *152 sion has overturned a decision by the Secretary of Labor to cite the owner-operator of a mine, as well as its independent contractor, for safety violations committed by the contractor. This court has long recognized the Secretary’s discretionary authority to cite the owner-operator, the independent contractor, or both for contractor violations. Because the Mine Act provides no meaningful standards against which to judge the Secretary’s decisions regarding which party to cite, the Commission is generally without authority to review such decisions. We therefore grant the Secretary’s petition for review and vacate the Commission’s ruling.
I
The Mine Act requires the Secretary of Labor, acting through the Mine Safety and Health Administration (MSHA), to promulgate mandatory safety and health standards for the mining industry and to conduct regular mine inspections. 30 U.S.C. §§ 811, 813(a). If a MSHA inspector discovers conditions that violate safety or health standards, § 104 of the Act directs the Secretary to issue a citation or an order to the mine’s “operator.” 30 U.S.C. §§ 814(a). The Act defines an “operator” as “any owner, lessee, оr other person who operates, controls, or supervises a ... mine or any independent contractor performing services or construction at such mine.” 30 U.S.C. § 802(d) (emphasis added). (The entities listed before the italicized “or” are also known as “production-operators.” 2 )
The Federal Mine Safety and Health Review Commission (FMSRHC) is an independent agency charged with adjudicating disputes under the Mine Act, including disputes over whether safety standards have been violated. See 30 U.S.C. §§ 815, 823. The Commission appoints administrative law judges (ALJs) to conduct trial-type proceedings to hear such disputes. See 30 U.S.C. § 823(d)(1). Any person aggrieved by a decision of an ALJ may request discretionary review by the Commission, see 30 U.S.C. § 823(d)(2)(A)®, and any person aggrieved by an order of the Commission may obtain review in this court, see 30 U.S.C. § 816(a)(1).
Twentymile owns and operates the Foi-del Creek Mine, an underground coal mine in Routt County, Colorado. In its capacity as owner-operator, Twentymile often uses independent contractors to undertake various projects at the mine. On August 14, 2001, Twentymile hired Precision Excavating, Inc., an independent contractor, to perform work on a refuse pile.
On August 30, 2001, MSHA Inspector Michael Havrilla conducted an inspection of the surface areas of the Foidel Creek Mine. During the course of his inspection, Havrilla observed that the equipment used by Precision’s employees violated six safety standards. Among the violations were a leaking diesel fuel tank on a pan scraper, and a ten-by-ten-inch opening on a service truck’s air compressor that permitted contact with the drive belts and pulley. When Havrilla discussed the violations with a Precision employee, he learned that Twen-tymile had not examined the contractor’s equipment prior to its use at the mine. See Secretary of Labor v. Twentymile Co., 25 F.M.S.H.R.C. 352, 356 (2003) (hereinafter ALJ Decision). Fearing that Precision’s violations might augur an increase in contractor violations, Havrilla decided that issuing citations to both Precision and Twentymile was the best way to guarantee mine safety. See id. at 356-57.
Precision, the independent contractor, did not contest the citations and paid the *153 $352 penalty assessed against it by MSHA. Twentymile,' however, contested the citations and the attendant $900 penalty. In a hearing before an ALJ, Twentymile stipulated that the conditions described in the citations constituted violations of the Mine Act, but argued that it was improper for the Secretary to cite it for violations committed by Precision. See id. at 353.
On July 7, 2003, the ALJ ruled in the Secretary’s favor. Citing Commission precedent, the ALJ held that, “in instances of multiple operators, the Secretary has wide enforcement discretion and ‘may, in general, proceed against an owner-operator, his contractor, or both.’ ” ALJ Decision, 25 F.M.S.H.R.C. at 358 (quoting Secretary of Labor v. Mingo Logan Coal Co., 19 F.M.S.H.R.C. 246, 249 (1997)). The ALJ found no abuse of discretion with respect to the Secretary’s decision to cite Twentymile as well as Precision. See id. at 359. Although he recognized the nonbinding nature of enforcement guidelines issued by the Secretary to identify when to charge an owner-operator, the ALJ found that “the citations easily fit within” the guidelines. Id. at 359; see id. at 359 n. 1 (referring to Enforcement Policy and Guidelines for Independent Contractors, App. A to Independent Contractors, 45 Fed.Reg. 44494, 44497 (July 1,1980) (hereinafter Enforcement &uidelines )). 3 In particular, the ALJ found that “Twentym-ile’s failure to inspect the equipment or ensure that the contractor inspected the equipment was an omission that contributed to the violations,” and that “Twentymile exercised sufficient control over the scraper and service truck” to warrant a citation. ALJ Decision, 25 F.M.S.H.R.C. at 360. The ALJ also credited the MSHA inspector’s statement that “he was concerned that safety hazards on contractors’ equipment were not being adequately addressed” because the “сited conditions were rather obvious,” and that “by issuing citations to Twentymile, the safety violations would get more immediate attention than if he only cited the contractor.” Id. at 359.
Twentymile appealed the ALJ’s decision to the Commission. See Secretary of Labor v. Twentymile Coal Co., 27 F.M.S.H.R.C. 260 (2005) (hereinafter Commission Decision). The company asserted that, under the Mine Act, an owner-operator is liable only for its own violations, and that the Secretary was therefore without authority to cite it for the violations of its independent contractor. See id. at 263. The Secretary responded that court and Commission precedents were directly to the contrary. See id. She further argued that her decision to cite Twen-tymile for Precision’s violations was not reviewable by the Commission because there was no meaningful standard against which to review her exercise of charging discretion. See id. at 265. In the event' that the Commission deemed her enforcement decision reviewable, the Secretary argued in the alternative that the citation was not an abuse of discretion. See id. at 266.
*154 The Commission reversed the ALJ’s decision and vacated the citations issued to Twentymile. See Commission Decision, 27 F.M.S.H.R.C. at 277. Its opinion began by agreeing with the Secretary’s (and the ALJ’s) view that “the Secretary generally may proceed against an owner-operator, an independent contractоr, or both, for violations by the independent contractor.” Id. at 263-64. Nonetheless, the Commission rejected the Secretary’s contention that her exercise of enforcement discretion was unreviewable. See id. at 265. And a majority of the Commission concluded that the Secretary had abused her discretion by citing Twentymile. See id. at 268. According to the majority, the Secretary’s decision to cite the owner-operator was an abuse of discretion because it was not made for reasons “consistent with the purpose and policies of the Mine Act.” Id. at 268 (internal quotation marks omitted). This was so, the Commission said, because: (1) “[t]he record show[ed] that the independent contractor was in the ‘best’ position to prevent the violations in question,” id. at 268; (2) “Twentymile did not have a significant, continuing involvement in the work specifically being performed at the refuse pile,” id. at 270; (3) Twentymile did not contribute to the violations “directly” or through a “significant” omission, id. at 270-71; and (4) none of the criteria listed in the Secretary’s Enforcement Guidelines was satisfied at “a significant threshold” level, id. at 273. 4
The Secretary of Labor now petitions this court for review of the Commission’s decision to vacate the citations filed against Twentymile. She contends that the Commission erred in holding that her decision to cite Twentymile for violations committed by Precision was reviewable; should we hold otherwise, the Secretary contends that her decision was not an abuse of discretion. Twentymile disputes both contentions, and it further challenges what it describes as the premise of the Secretary’s nonreviewability argument: that she has authority to cite an owner-operator for safety violations committed by its independent contractor. Because the Secretary’s authority is indeed the premise of her argument, we consider that issue first and then proceed to examine the issue of reviewability.
II
Wе can make relatively short work of the question of the Secretary’s authority to cite owner-operators for violations committed by their contractors because it is a question that this circuit has already answered. Indeed, Twentymile concedes that “decisions from this Court grant the Secretary the discretion to cite both the production-operator and the independent contractor for the violation of the independent contractor.” Respondents’ Br. 26. Although Twentymile urges us to rule to the contrary, such a disposition is plainly beyond the power of a panel of this court.
See, e.g., Ranger Cellular v. FCC,
This circuit’s seminal opinion regarding the authority of the Secretary is
Brock v. Cathedral Bluffs Shale Oil Co.,
“[0]perator” means any owner, lessee, or other person who operates, controls, or supervises a coal or other mine or any independent contractor performing services or construction at such mine [.]
30 U.S.C. § 802(d) (emphasis added);
see Cathedral Bluffs,
Two years after
Cathedral Bluffs,
in
International Union, United Mine Workers of America v. FMSHRC
(“
UMWA
”), we observed thаt “all of the courts that have had occasion to address the question have held that multiple operators are jointly liable under the Act[,][o]r, put differently, the owner of a mine is liable without regard to its own fault for violations committed or dangers created by its independent contractor.”
“Without exemption or exclusion, § 819 makes the operator of a coal mine in which a violation occurs subject to a civil penalty .... Th[is] section[ ], when read with the definition of operator, impose[s] liability on the owner or lessee of a mine regardless of who violated the Act .... ”
Id.
at 83 (quoting
BCOA,
Ill
Having concluded that the Secretary of Labor has authority tо cite an owner-oper
*156
ator for safety violations committed by its contractor, we next consider whether Twentymile may contest the Secretary’s discretionary decision to do so. Because the reviewability of the Secretary’s charging decision is a legal question, we decide the issue de novo.
See Secretary of Labor v. Keystone Coal Mining Corp.,
A
Although there is a strong presumption that agency action is reviewable,
see Citizens to Preserve Overton Park, Inc. v. Volpe,
In determining “whether a matter has been committed solely to agency discretion, we consider both the nature of the administrative action at issue and the language and structure of the statute that supplies the applicable legal standards for reviewing that action.”
Drake,
Indeed, with respect to criminal charging decisions, the Supreme Court has made clear that the government’s decision “as to whom to prosecute” is generally unreviewable.
Wayte v. United States,
This broad discretion rests largely on the recognition that the decision to prosecute is particularly ill-suited to judicial review. Such factors as the strength of the case, the prosecution’s general deterrence value, the Government’s enforcement priorities, and the case’s relationship to the Government’s overall enforcement plan are not readily susceptible to the kind of analysis the courts аre competent to undertake.
Of course, if the Mine Act provided a “meaningful standard against which to judge the agency’s exercise of discretion,” the situation would be different.
Chaney,
But the Mine Act does not provide a meaningful standard. Under the Act, the Secretary’s charging discretion is as uncabined as that of a United States Attorney under the Criminal Code. Section 104(a) simply provides that “[i]f, upon inspection or investigation, the Secretary or his authorized representative believes that an operator of a coal or other mine subject to this chapter has violated this chapter, ... he shall, with reasonable promptness, issue a citation to the operator.” 30 U.S.C. § 814(a). As we have noted, the Act defines “operator” as “any owner, lessee, or other person who operates, controls, or supervises a ... mine or any independent contractor performing services ... at such mine.” 30 U.S.C. § 802(d) (emphasis added). Nothing in this language instructs the Secretary of Labor which of several jointly-liable operators to charge, any more than the Criminal Code tells a U.S. Attorney which of several co-conspirators to prosecute. Rather, the *158 statute is “utterly silent on the manner in which the [agency] is to proceed against a particular transgressor.” Baltimore Gas & Elec. Co. v. FERC, 252 F.3d 456, 461 (D.C.Cir.2001). And, because of that silence, the Secretary’s charging decisions are unreviewable. 7
The Commission, however, hears sounds in the silence. In support of its conclusion that the Secretary’s charging decisions are reviewable, the Commission purported tо discern the following standard: The Secretary’s decision to cite an owner-operator, the Commission said, must be “made for reasons consistent with the purpose and policies of the Mine Act.”
Commission Decision,
27 F.M.S.H.R.C. at 266 (internal quotation marks omitted). That phrase is nowhere to be found in the Act itself, nor does it offer a particularly meaningful standard. Indeed, were we to regard it as one, we would have to hold all agency decisions under all statutes reviewable, as all legislation has “purpose[s] and policies.”
Cf. Baltimore Gas,
But the most pernicious aspect of employing this purported standard as a check on charging decisions is that it invites the reviewing body to substitute its views of enforcement policy for those of the Secrеtary, a power that — as we discuss in Part III.B- — •the Commission does not possess. In fact, that is precisely what the Commission did in this case. It found that the Secretary’s decision to cite the owner-operator was not “consistent with the purpose and policies of the Mine Act” because: (1) “the independent contractor was in the ‘best’ position to prevent the violations in question,” Commission Decision, 27 F.M.S.H.R.C. at 268; (2) “Twentymile did not have a significant, continuing involvement in the work specifically being performed at the refuse pile,” id. at 270; (3) Twentymile did not contribute to the violations “directly” or through a “significant” omission, id. at 270-71; and (4) none of thе criteria listed in the Secretary’s enforcement guidelines was satisfied at “a significant threshold” level, id. at 273. Yet, because the Mine Act subjects an owner-operator to strict liability for its contractor’s violations, see supra Part II, nothing in the statute bars the Secretary from charging an owner-operator even if it was not in the “best” position to prevent a violation, did not have a “significant, continuing involvement” in the contractor’s work, and did not contribute “directly” or “significantly]” to the violation. And there is certainly nothing in the Mine Act that requires the Secretary to impose a “significant threshold” test on her own enfоrcement guidelines.
To be sure, “[t]his Court has noted that judicially manageable standards may be found in formal and informal policy state
*159
ments and regulations as well as in statutes.”
Steenholdt,
In
Cathedral Bluffs,
the court — as we do here — reversed the Commission’s dismissal of a citation issued by the Secretary tо an owner-operator for a safety violation committed by its independent contractor.
See id.
at 534. As is the case in part here, the Commission’s dismissal was based on its view that the Secretary’s decision to cite was inconsistent with the
Enforcement Guidelines. See id.
In finding the
Guidelines
nonbinding, then-judge Scalia’s opinion for the court stressed that the “question pertains to an agency’s exercise of its enforcement discretion — an area in which the courts have traditionally been most reluctant to interfere.”
Id.
at 538 (citing
Chaney,
B
The Commission held, and Twentymile asserts, that the case law regarding nonre-viewability does not apply to this matter because of two specific provisions of the Mine Act. See Commission Decision, 27 F.M.S.H.R.C. at 265-66.
First, the Commission noted that cases such as Chaney and its progeny “involve preclusion of review under section 701(a)(2) of the Administrative Procedure Act,” and that “section 507 of the Mine Act expressly provides that section 701 of the APA does not apply to Commission proceedings.” Id. at 265 (internal citation omitted). Section 507 does indeed state that, “[ejxcept as otherwise provided in this chapter, the provisions of ... sections 701-706 of Title 5 shall not apply to the making of any order, notice, or decision made pursuant to this chapter, or to any proceeding for the review thereof.” 30 U.S.C. § 956.
Contrary to the view of the Commission, however, the fact that § 701(a)(2) itself is inapplicable does not mean that the principles underlying it are also inapplicable. Rather, as the Supreme Court has explained, “the Administrative Procedure Act ...
codifies
the nature and attributes of judicial review, including
the traditional principle
of its unavailability ‘to the extent that ... agency action is committed to agency discretion by law.’ ”
ICC v. Brotherhood of Locomotive Eng’rs,
Second, the Commission contended that the Mine Act gives it express authority to review the Secretary’s discretionary enforcement decisions and to formulate mine safety policy. See Commission Decision, 27 F.M.S.H.R.C. at 266. The Commission based this holding on Mine Act § 113, which provides that any person aggrieved by a decision of an ALJ may file a petition for Commission review on the ground that “a substantial question of law, policy or discretion is involved.” 30 U.S.C. § 823(d)(2) (A) (ii) (IV).
This circuit, however, has already rejected the contention that § 113 gives the Commission authority to determine policy issues.
See Energy West Mining Co. v. FMSHRC,
Both
Energy West
and
Mutual Mining
are part of a line of cases that anticipated, and then followed, the Supreme Court’s decision in
Martin v. Occupational Safety & Health Review Commission,
We have previously, and repeatedly, applied Martin’s analysis to the Mine Act.
12
We do so here as well. As is true under the OSH Act, “enforcement of the [Mine] Act is the sole responsibility of the Secretary,”
IV
We conclude that the Commission is generally without authority to review the Secretary’s discretionary decisions regarding whether to cite owner-operators, their independent contractors, or both for safety violations committed by the independent contractors. Suсh decisions are not, of course, wholly immune from review. The Secretary’s discretion, like that of a prosecutor, remains “subject to constitutional constraints,” including those “imposed by the equal protection component of the Due Process Clause of the Fifth Amendment.”
Armstrong,
Moreover, the Commission retains authority to adjudicate — subject to the appropriate standard of review 13 — whether safety violations have in fact occurred. See 30 U.S.C. §§ 815(d), 823(d). In this case, however, Twentymile has stipulated that the conditions cited by the Secretary constitute violations of safety standards. See ALJ Decision, 25 F.M.S.H.R.C. at 353. We therefore grant the Secretary’s petition for review. The decision of the Commission, which reversed the decision of the ALJ and vacated the citations issued to Twentymile, is itself vacated and the citations are reinstated.
So ordered.
Notes
. See Secretary of Labor v. Twentymile Coal Co., 27 F.M.S.H.R.C. 260, 278 (2005) (Jordan, Comm’r, concurring and dissenting).
. See Independent Contractors, 45 Fed.Reg. 44494, 44494 (July 1, 1980).
. The Enforcement Guidelines state:
[A]s a general rule, a production-operator may be properly cited for a violation involving an independent contractor: (1) when the production-operator has contributed by either an act or an omission to the occurrence of a violation in the course of an independent contractor's work, or (2) when the production-operator has contributed by either an act or omission to the continued existence of a violation committed by an independent contractor, or (3) when the production-operator’s miners are exposed to the hazard, or (4) when the production-operator has control over the condition that needs abatement.
45 Fed.Reg. at 44497.
. The Commission relied on the final point notwithstanding its acknowledgment that "the Enforcement Guidelines are not binding on the Secretary.'' Commission Decision, 27 F.M.S.H.R.C. at 273 n. 19.
. Section 110 of the Mine Act, which under the Coal Act was 30 U.S.C. § 819 (1976), states:
The operator of a coal or other mine in which a violation occurs of a mandatory health or safety standard ... shall be assessed a civil penalty by the Secretary....
30 U.S.C. § 820(a) (emphasis added).
.
See, e.g., Lincoln,
.
See Lincoln,
. As discussed above, see supra note 4, the Commission applied the Enforcement Guidelines to the Secretary's decision to charge Twentymile notwithstanding its acknowledgment that "the Enforcement Guidelines are not binding on the Secretary.” Commission Decision, 27 F.M.S.H.R.C. at 273 n. 19.
.
See Lincoln,
.
See Sierra Club v. Whitman,
. See Cathedral Bluffs,
.
See, e.g., Secretary of Labor
v.
Twentymile Coal Co.,
. As we have explained: “Under the statutory scheme, the Commission is required to accord deference to the Secretary's interpretations of the law and regulations. And while it may reverse a decision by an ALJ for legal error, the Commission must uphold an ALJ’s factual determinations if they are supported by substantial evidence.”
RAG Cumberland,
