concurring in the judgment.
Although I concur in much of the Court’s reasoning and in its holding that “the Commission is not empowered to issue, based upon a single set of circumstances, a series of summary orders which would suspend trading beyond the initial 10-day period,” ante, at 106,1 cannot join the Court’s opinion because of its omissions and unfortunate dicta.
I
The Court’s opinion does not reveal how flagrantly abusive the Security and Exchange Commission’s use of its § 12 (k) authority has been. That section authorizes the Commission “summarily to suspend trading in any security ... for a period not exceeding ten days . . . .” 15 U. S. C. § 78l (k) (1976 ed.). As the Court says, this language “is persuasive in and of itself” that 10 days is the “maximum time period for which trading can be suspended for any single set of circumstances.” Ante, at 112. But the Commission has used § 12 (k), or its predecessor statutes, see ante, at 105 n. 1, to suspend trading in a security for up to 13 years. See App. to Brief for Canadian Javelin, Ltd., as Amicus Curiae la. And, although the 13-year suspension is an extreme example, the record is replete with suspensions lasting the better part of a year. See App. 184-211. I agree that § 12 (k) is clear on its face and that it prohibits this administrative practice. But even if § 12 (k) were unclear, a 13-year suspension, or even a 1-year suspension as here, without notice or hearing so obviously violates fundamentals of due process and fair play that no *124reasonable individual could suppose that Congress intended to authorize such a thing. See also 15 U. S. C. § 78l (j) (1976 ed.) (requiring notice and a hearing before a registration statement can be suspended), discussed ante, at 121-122.
Moreover, the SEC’s procedural implementation of its § 12 (k) power mocks any conclusion other than that the SEC simply could not care whether its § 12 (k) orders are justified. So far as this record shows, the SEC never reveals the reasons for its suspension orders.1 To be sure, here respondent was able long after the fact to obtain some explanation through a Freedom of Information Act request, but even the information tendered was heavily excised and none of it even purports to state the reasoning of the Commissioners under whose authority § 12 (k) orders issue.2 Nonetheless, when the SEC finally *125agreed to give respondent a hearing on the suspension of Canadian Javelin stock, it required respondent to state, in a verified petition (that is, under oath) why he thought the unrevealed conclusions of the SEC to be wrong.3 This is obscurantism run riot.
Accordingly, while we today leave open the question whether the SEC could tack successive 10-day suspensions if this were necessary to meet first one and then a different emergent situation, I for one would look with great disfavor on any effort to tack suspension periods unless the SEC concurrently adopted a policy of stating its reasons for each suspension. Without such a statement of reasons, I fear our holding today will have no force since the SEC’s administration of its suspension power will be reviewable, if at all, only by the circuitous and time-consuming path followed by respondent here.
II
In addition, I cannot join the Court’s reaffirmance of Adamo Wrecking’s increasingly scholastic approach to the use of administrative practice in interpreting federal statutes. See ante, at 117-118. This reaffirmance is totally unnecessary in this case for, as the Court notes, whatever that administrative construction might be in this case, it is “inconsistent with the statutory mandate,” ante, at 118, which is clear on the face of the statute. Ante, at 112.
Worse, however, is the Court’s insistence that, to be credited, an administrative practice must pay “ 'specific attention to the statutory authorization’ ” under which an agency purports to operate. Ante, at 117, quoting Adamo Wrecking Co. v. United States, 434 U. S. 275, 287 n. 5 (1978). As my Brother Stevens *126noted in dissent in Adamo, see id., at 302, Norwegian Nitrogen Co. v. United States, 288 U. S. 294 (1933)— perhaps our leading case on the use of administrative practice as a guide to statutory interpretation — says not a word about attention to statutory authority. Nor does it reduce the value of administrative practice to its “persuasive effect” as the Court would apparently do here. Instead, as I understand the case, Norwegian Nitrogen focuses on the “contemporaneous construction of a statute by the men charged with the responsibility of setting its machinery in motion,” id., at 315, precisely because their action is itself evidence of assumptions — perhaps unspoken by either the administrators or Congress — brought to a regulatory problem by all involved in its solution. Indeed, common experience tells us that it is assumptions which everyone shares which often go unspoken because their very obviousness negates the need to set them out.
Therefore, while I do not dispute that well-reasoned administrative opinions which pay scrupulous attention to every jot and tittle of statutory language are more persuasive than unexplained actions — and certainly more in keeping with a norm of administrative action that ought to be encouraged— I cannot dismiss, as the Court apparently does, less well-reasoned, or even unexplained, administrative actions as irrelevant to the meaning of a statute.
The only document made public by the SEC at the time it suspends trading in a security is a “Notice of Suspension of Trading.” Numerous copies of this notice are included in the Appendix and each contains only the boilerplate explanation:
“It appearing to the Securities and Exchange Commission that the summary suspension of trading in such securities on such exchange and otherwise than on a national securities exchange is required in the public interest and for the protection of investors; [therefore, trading is suspended].”
See App. 11, 13, 16, 19, 21, 23, 25, 27, 30, 33, 36, 39, 41, 44, 47, 50, 53, 56, 59, 62, 65, 67, 69, 71, 73, 76, 79, 82, 85, 88, 91, 94, 97, 100, 103, 106. The sole exception to this monotonous pattern is the notice which issued after respondent lodged his verified petition with the SEC. That notice recounted the allegations of the petition and stated in some detail why it was necessary to continue the suspension of Canadian Javelin stock. See id., at 109-110.
In each instance, the explanation consists only of memoranda from the SEC’s Division of Enforcement to the Commission. See, e. g., id., at 12, 14, 15. In at least one instance, the memorandum postdates the public notice of suspension. Compare id., at 11 with id., at 12. In no case is there a memorandum from, the Commission explaining its action. The Court apparently assumes that the memoranda of the Division of Enforcement adequately explain the Commission’s action, although the basis for any such assumption is not apparent. Moreover, since the recommendations *125portion of each memoranda is excised, presumably as permitted (but not required) by Exemption 5 of the Freedom of Information Act, see EPA v. Mink, 410 U. S. 73, 89 (1973), there is no statement of reasons in any traditional sense in any of the memoranda.
See Brief for Respondent 19; App. to Brief for Respondent 20a-21a.