dissenting.
This case presents the question whether the Interstate Commerce Commission (Commission) may nullify a motor carrier tariff at any time after it has become effective. Such nullification renders the carrier liable to shippers for the amount by which the rejected rate exceeds the last rate the carrier has lawfully filed. The Court quite correctly reasons *372that 49 U. S. C. § 10762(e) does not authorize the Commission to reject effective tariffs. See ante, at 361-364. Reading § 10762(e) to authorize such action would indeed give the Commission an “unbridled discretion” that Congress did not intend it to have. See ante, at 363. However, after having correctly rejected § 10762(e) as a basis for the proposed rejection power, the Court then mysteriously concludes that the power is within the Commission’s “discretionary power” to ensure that shippers adhere strictly to their approved rate bureau agreements. Ante, at 367. I frankly do not understand how this alternative “discretionary power” rationale better reins in the Commission’s discretion. Accordingly, I dissent.
I
The Court starts with the proposition that the enumeration of certain Commission powers in the Interstate Commerce Act, as amended, 49 U. S. C. § 10101 et seq., does not necessarily exclude others not expressly listed. See ante, at 364-365. I have no quarrel with that proposition. Like most agencies, the Commission is authorized to prescribe regulations to carry out its statutory duties. 49 U. S. C. § 10321(a). The Commission’s efforts to interpret and implement the tariff filing provisions therefore deserve considerable judicial deference. See American Trucking Associations, Inc. v. United, States, 344 U. S. 298, 311 (1953); see generally United States v. Chesapeake & Ohio R. Co., 426 U. S. 500 (1976); Trans Alaska Pipeline Rate Cases, 436 U. S. 631 (1978). But this rule of deference has never been equated with a “discretionary power” in the Commission to place conditions on its acceptance of proposed tariffs. I think the Court misreads its prior cases in finding such authority today.
The Court did not, as today’s opinion asserts, approve the concept of “discretionary power” of the Commission in United States v. Chesapeake & Ohio R. Co., supra. In that case, the Commission proposed to allow an immediate rate in*373crease on the condition that the benefited rail carriers devote to certain designated uses the additional revenues earned during the 7-month period the rates would otherwise have been suspended. Though the Commission had no express power to place conditions on the use of these revenues, the Court concluded that qualifying immediate acceptance in this manner was “a legitimate, reasonable, and direct adjunct [of] the Commission’s explicit statutory power to suspend rates pending investigation.” 426 U. S., at 514. Delaying implementation of the new tariffs would only have frustrated Congress’ desire to improve the condition of the railroads. Thus, the Commission’s decision to condition its acceptance on use of the moneys earned during the 7-month suspension period was “an alternative tailored far more precisely to the particular circumstances presented.” Ibid.
Nor did the Trans Alaska Pipeline Rate Cases, supra, approve any principle of inherent Commission authority. In these cases, the Commission proposed to allow the owners of the Trans Alaska Pipeline System to implement immediately rates on condition that the carriers refund any amounts collected during the period the rates would otherwise have been suspended and later determined to be unlawful. The Court sustained the Commission’s efforts, finding that the condition was a power “ ‘ancillary’ to [the] suspension power” and that immediate implementation would further Congress’ policy of early development and delivery of oil from Alaska’s North Slope. 436 U. S., at 654-655. Again, the Court deferred to the Commission’s efforts, but only because the Commission had implemented an alternative that was carefully tied to the statutory suspension power and narrowly tailored to the particular circumstances presented. Id., at 655.
Thus, Chesapeake & Ohio R. Co. and Trans Alaska Pipeline Cases support neither the remedy the Commission has proposed to implement here nor the power on which the Court suggests that it can be based. In contrast to the conditions imposed in those cases, the Commission’s proposed *374retroactive rejection power is not a “direct adjunct” of the statutory suspension power. The Commission claims the power retroactively to reject a tariff at any time, not just during the 7-month period it could otherwise have suspended and investigated the proposed rates. More importantly, neither case even mentions the principle of “discretionary power” on which the Court today relies. Rather, the Court in both cases gave traditional judicial deference to the Com-' mission’s use of its express statutory powers. The idea of a boundless “discretionary power” was simply not considered.
II
Perhaps recognizing the open-ended character of the regulatory principle it announces, the Court suggests that two limiting criteria will cabin the Commission’s discretionary authority. First, the Court proposes that the authority must be exercised to further a specific statutory mandate. Ante, at 367. Second, the Court proposes that the exercise of the authority must be directly and closely tied to that mandate. Ibid. Whatever the merits of these criteria, they definitely are not satisfied in the circumstances of this case.
A
The Court points to the Motor Carrier Act of 1980, Pub. L. 96-296, 94 Stat. 793, as the statutory mandate that the Commission’s retroactive rejection authority is being used to further. According to the Court, the Congress enacting this legislation left to the Commission discretionary authority to fashion remedial powers necessary to ensure that shippers adhere strictly to their approved rate bureau agreements. Ante, at 368. However, an examination of the history behind this legislation unambiguously refutes this view.
Prior to the enactment of the Motor Carrier Act, the Commission had been attempting to curtail drastically the motor carriers’ opportunities to engage in collective ratemaking. In one rulemaking proceeding, for example, the Commission had proposed exactly what Congress itself had earlier re-*375jeeted — namely, to apply to motor carrier rate bureaus the severe restrictions on collective ratemaking authority statutorily imposed on rail rate bureaus by the Railroad Revitalization and Regulatory Reform Act of 1976. See 43 Fed. Reg. 1809 (1978). In another instance, the Commission had proposed to review every individual ratemaking agreement to determine if continued approval would be warranted under new Commission standards. See id., at 1666. And in 1979, when budgetary constraints and increased filings caused it to change its tariff monitoring practices, the Commission twice asserted that retroactive tariff rejection was necessary to combat anticompetitive practices in the motor carrier industry. See 44 Fed. Reg. 58511, 58512, 60122, 60123-60124 (1979). The 1980 Congress shared the Commission’s desire to increase competition in the motor carrier industry, but it rejected the Commission’s attempts to create that competition on its own initiative.
Well aware that the “Commission ha[d] recently embarked upon a series of reviews of rate bureau agreements to determine whether they should be continued and, if so, under what conditions,” H. R. Rep. No. 96-1069, p. 27 (1980), Congress made clear that it wanted to reduce the Commission’s regulatory authority over motor carrier rate bureau practices.
“[I]n order to reduce the uncertainty felt by the Nation’s transportation industry, the . . . Commission [is] given explicit direction for regulation of the motor carrier industry and well-defined parameters within which it may act pursuant to congressional policy; . . . the . . . Commission should not attempt to go beyond the powers vested in it by the Interstate Commerce Act . . . and other legislation enacted by Congress.” 94 Stat. 793.
Senator Cannon, one of the sponsors of the 1980 Act, explained:
“[Ljegislation is desperately needed to clarify the existing regulatory uncertainty that plagues the industry and those who care about it. . . . This bill gives specific direc*376tion to the Interstate Commerce Commission and we expect those directions to be followed. Where the Commission is to be given more discretion, it is clear from the statute, but in most cases, the discretion is eliminated.” 126 Cong. Rec. 7777 (1980).
Representative Harsha gave a similar explanation to his colleagues in the House:
“For too long Congress has basically been on the sidelines, while the Interstate Commerce Commission exercised unduly wide discretion in regulating the Nation’s motor carrier industry. . . . [I]n the past several years, it has made changes in the regulatory system on its own initiative[,] in the absence of congressional guidance, if not consultation.
“It is not the intent of the committee, and I am certain that it is not the will of Congress, that while we reduce the amount of needless regulation in the trucking industry, we increase the regulatory powers of ICC bureaucrats.
“Therefore, [the bill] give[s] clear guidelines to the ICC on how to administer the law. In so doing, the committee expects the Commission to stay within the explicit powers invested by the new statute. ...” Id., at 15585.
These sentiments were echoed in the Committee Reports of each congressional chamber. See H. R. Rep. No. 96-1069, swpra, at 29; S. Rep. No. 96-641, p. 31 (1980).
To be sure, Congress wanted the Commission to “retain and enforce existing regulations as to the processing of loss, damage, and overcharge claims . . . .” H. R. Rep. No. 96-1069, swpra, at 40. But Congress expressed a strong disapproval of all of the Commission’s pre-1980 regulatory innovations, and the retroactive rejection remedy had been prominent among them. See 44 Fed. Reg. 60122, 60123-*37760124 (1979); see also Motor Carrier Rate Bureaus — Implementation ofP. L. 96-296, 3641. C. C. 464, 503 (1980) (Commissioner Gilliam, concurring); 45 Fed. Reg. 55742 (1980) (Commissioner Stafford, dissenting). Thus, while the 1980 Congress may not have intended to diminish the Commission’s existing enforcement authority, there can be no doubt about its intention to prevent the Commission from unilaterally enlarging its own discretionary powers.
B
The Court contends, nevertheless, that the rejection power is directly and closely tied to 49 U. S. C. § 10762(e). Ante, at 369-371. On this view, nullification of effective tariffs is necessary both to ensure that motor carriers comply with the guidelines established by Congress and to stimulate competitive pricing beyond the bounds of the motor-carrier immunity granted in § 10706(b)(3). Though resulting awards could easily surpass the damages for which carriers may be held liable under the antitrust laws, and could therefore convert the Commission into the Federal Government’s most potent antitrust enforcer, the Court concludes that deference to the Commission’s efforts to enforce § 10706(b)(3), is not inappropriate. Ante, at 370-371. I must disagree.
Even if Congress had left the Commission discretion to fashion some new remedies to enforce § 10706(b)(3), there is much reason to believe that the retroactive rejection power could not properly be among them. As previously noted, the Commission proposed to use this same retroactive rejection remedy for similar purposes prior to the 1980 legislation. See supra, at 375. The Commission was concerned, because of budgetary constraints and increased tariff filings, that it could not catch all improper tariffs and that carriers would have incentives to exceed their limited immunity from the antitrust laws. Ibid. The 1980 Congress was well aware of the Commission’s concerns and of the remedies the Commission then had available to it. Yet Congress did not include *378the rejection power in its comprehensive restructuring of the rate bureau regulatory system. Rather, it emphasized that it did not want to increase the power of the Commission. Perhaps the Commission is correct in asserting that shippers lack sufficient incentives to ensure optimal enforcement of the antitrust laws. But that is a gap Congress obviously wanted the Department of Justice, not the Commission, to fill. See 364 I. C. C., at 503 (Commissioner Gilliam, concurring); 46 Fed. Reg. 2295 (1981) (Commissioner Clapp, concurring). Making the Commission the most potent enforcer of the Nation’s antitrust laws is hardly compatible with the congressional antagonism toward the Commission’s specific pre-1980 deregulation initiatives.
Indeed, it is easy to see why Congress would not have included a retroactive rejection power among the arsenal of powers available to the Commission. Part of the Motor Carrier Act’s purpose was, as the Commission asserts, to limit the rate bureaus’ freedom to engage in collusive behavior. Conversely, however, the 1980 Act was equally intended to promote certainty in industry pricing and to protect carriers’ reliance on filed tariffs. In the motor carrier industry, goods are shipped, revenues collected, and business plans formulated in reliance on these tariffs. In 1980, Congress apparently continued to believe that effective national transportation policy requires that carriers be able to rely on their filed rates and know that liability for charging those rates will result only if shippers show actual damage. Congress has deliberately encouraged carriers, within limits, to set prices collectively, and has insulated them from the proscriptions of the antitrust laws when they do so. The rejection power, by contrast, confronts carriers with a large and uncertain liability and discourages the collective price setting clearly contemplated by the Act. The rejection power “create[s] a legalized, but endless, chain of departures from [filed] tariffs]; . . . destroy[s] the equality and certainty of rates, and, contrary to the statute, . . . make[s] the carrier liable for *379damages beyond those inflicted and to persons not injured.” Davis v. Portland Seed Co., 264 U. S. 403, 421 (1924). The power is, therefore, incompatible with collective aspects of the rate-setting scheme Congress intended to promote.
I — I I — I I — I
What the Commission really seeks is a remedy that is not statutorily authorized but that is alleged to be administratively needed. The need, of course, is far from clear, given the impressive array of prescriptive powers, overcharge assessments, damages remedies, and civil and criminal fines at the Commission’s disposal. See 49 U. S. C. §§ 11705(b) (1) — (3), 10704, 11901(b), 11914(b). If the Commission believes that it needs additional remedial power to enforce the rate bureau provisions, it should seek such power from Congress. But this Court is no more authorized than is the Commission to rewrite the law. Since that is what today’s decision allows the Commission to do, I respectfully dissent.