delivered the opinion of the Court.
This case draws in question the propriety of the issuance of a federal injunction restraining petitioner, a state officer, from giving evidence in a pending state criminal prosecution and a state administrative proceeding.
The facts, as found by the two lower courts, are as follows. About 8:30 one Saturday morning in September *3931959 federal Customs officers observed respondent, a hiring agent and longshoreman licensed by the Waterfront Commission of New York Harbor, enter a deserted pier, carry out a cardboard carton, and place it in a car parked at the pier entrance. The officers, who were concerned about the recent frequency of thefts, particularly of liquor, in the New York waterfront area, followed respondent's car for a short distance and then ordered him to stop. A search of the automobile revealed that the cardboard carton contained only empty soda bottles, but that the glove compartment contained a number of spark plugs and windshield wipers, some of which were stamped “Made in England.” Respondent was asked whether he had obtained any liquor from the piers, and he admitted that he had six or eight bottles at home which he had purchased from members of ships' crews who in turn, he said, had bought them from ships’ stores.
The agents then took respondent into custody; he was brought to the Customs office, denied permission to use the telephone, and questioned until shortly before 11 a. m. During this period he signed a document consenting to a search of his home by the Customs officers, who had told him that the consent form was unnecessary since they already had enough information to warrant a search but that he might as well sign it to save them trouble. He had at first refused to sign such a consent without consulting a lawyer. The agents then drove respondent to his home in New Jersey and, without a search warrant, gave it a thorough search, which uncovered some 75 bottles of liquor, a Stenorette tape recording machine made in West Germany, and various other items of apparent foreign origin, such as perfumes, linens, costume jewelry, etc. These articles, thought to have been illegally acquired, were brought'back to Customs headquarters in New York, where, starting about 4 p. m., respondent was again questioned.
*394By this time the Waterfront Commission, a bi-state agency of New York and New Jersey1 which worked in close cooperation with the Customs Service in matters of law enforcement on the waterfront, had been informed of respondent’s arrest, and two Commission detectives were present when the interrogation resumed. Petitioner Cleary was one of these detectives. After respondent had revealed that he maintained a tool room in the basement of an apartment house in New York, petitioner and a Customs officer accompanied respondent to this tool room, but nothing suspicious was discovered and they returned to Customs headquarters at 5:45 p. m.
After he had been told that he did not have to make a statement, respondent was sworn and interrogated by Customs officers in the presence of a Customs Service reporter, who recorded the questions and answers verbatim. Petitioner was present and could have participated in the questioning, though he did not do so.2 Respondent admitted that with the exception of a few items that he had purchased from crew members most of the articles seized at his home had been taken by him from piers where he worked. He also said that he had taken the Stenorette tape recorder from a lighter moored at one of the piers. At 7:30 p. m. respondent was released.
No charges were lodged against respondent by the federal authorities. But a month later he was arrested by the New York City police on a charge of grand larceny for the theft of the Stenorette tape recorder, and shortly thereafter the Waterfront Commission temporarily suspended his licenses as hiring agent and longshoreman. The criminal charge was subsequently reduced to petit *395larceny and scheduled for trial in the Co.urt of Special Sessions of New York City. A hearing looking to the revocation of respondent’s licenses was deferred by the Waterfront Commission pending the outcome of the criminal case.
After the petit larceny charge had been set for trial, respondent instituted the present action in the United States District Court for the Southern District of New York seeking to enjoin the federal Customs officers and petitioner from using in evidence any of the seized property or his incriminating statement, and from testifying with respect thereto, in the state criminal trial or Waterfront Commission proceeding. He also sought return of the seized property.3 The basis for the action was the claim that the seized property and the incriminating statement were the products of illegal conduct on the part of the federal officers.
The District Court granted such relief, limited however, to the property seized at respondent’s home, to the incriminatory statement made following his arrest, and to testimony respecting these matters.4 It held that the search and seizure at respondent’s home violated Rule 41 (a) of the Federal Rules of Criminal Procedure,5 in that it had *396been made without a search warrant, and that his incriminating statement had been procured in violation of Rule 5 (a) of those Rules,6 in that respondent had not been taken before a United States Commissioner within a reasonable time after his arrest, and was also “the result ... of the illegal search and seizure.” In consequence of these illegalities an injunction against the federal officers was thought to follow. An injunction against petitioner was deemed necessary to make the injunction against the federal officials effective. 189 F. Supp. 237. The Court of Appeals affirmed by a divided vote. 293 F. 2d 368. Since the use of federal equity power in the premises presented important questions touching upon federal-state relationships in the realm of state criminal prosecutions, we brought the case here. 368 U. S. 984.
Accepting for present purposes the holdings of the two lower courts with respect to the conduct and enjoin-ability of the federal officers, we nevertheless conclude that the injunction against this petitioner was improvidently issued.7
*397Courts of equity traditionally have refused, except in rare instances, to enjoin criminal prosecutions. This principle “is impressively reinforced when not merely the relations between coordinate courts but between coordinate political authorities are in issue.” Stefanelli v. Minard, 342 U. S. 117, 120. It has been manifested in numerous decisions of this Court involving a State’s enforcement of its criminal law. E. g., Pugach v. Dollinger, 365 U. S. 458; Douglas v. City of Jeannette, 319 U. S. 157; Watson v. Buck, 313 U. S. 387; Beal v. Missouri Pac. R. Co., 312 U. S. 45. The considerations that have prompted denial of federal injunctive relief affecting state prosecutions were epitomized in the Stefanelli case, in which this Court refused to sanction an injunction against state officials to prevent them from using in a state criminal trial evidence seized by state police in alleged violation of the Fourteenth Amendment:
“[W]e would expose every State criminal prosecution to insupportable disruption. Every question of procedural due process of law — with its far-flung and undefined range — would invite a flanking movement against the system of State courts by resort to the federal forum, with review if need be to this Court, to determine the issue. Asserted unconstitutionality in the impaneling and selection of the grand and petit juries, in the failure to appoint counsel, in the admission of a confession, in the creation of an unfair trial atmosphere, in the misconduct of the trial court— all would provide ready opportunities, which conscientious counsel might be bound to employ, to subvert the orderly, effective prosecution of local crime in local courts. To suggest these difficulties is to recognize their solution.” 342 U. S., at 123-124.
*398The two courts below recognized the validity of these considerations but thought that injunctive relief was nonetheless required by Rea v. United States, 350 U. S. 214. In that case the accused had been indicted in a federal court and had moved for an order under Rule 41 (e) of the Federal Rules of Criminal Procedure suppressing the use in evidence of certain narcotics seized under a search warrant invalid on its face. The District Court granted the motion. Despite the order, however, one of the federal officers who had secured the search warrant caused the accused to be rearrested and charged, in a state court, with possession of the same narcotics in violation of a state statute, and threatened to make the State’s case by his testimony based on the evidence seized under the illegal federal warrant. The accused then moved in the Federal District Court to enjoin the federal agent from testifying in the state proceeding. This Court, invoking its “supervisory powers over federal law enforcement agencies” (id., at 216-217), reversed the denial of an injunction and directed that the requested relief be granted in order to prevent frustration of the Federal Rules under which suppression had been ordered.8 Both lower courts in the present case evidently took Rea to mean that federal officers transgressing the Federal Rules of Criminal Procedure may always be enjoined from utilizing their ill-gotten gains in a state criminal prosecution against the victim or from directly or indirectly passing them along to state authorities for such use.9
We need not, however, determine in this instance the correctness of the lower courts’ broad reading of the Rea *399case, cf. Wilson v. Schnettler, 365 U. S. 381, on the basis of which the federal officers here were enjoined.10 For in any event Rea does not support the injunction against this petitioner, a state official. The Court in Rea was at special pains to point out that the federal courts were not there “asked to enjoin state officials nor in any way to interfere with state agencies in enforcement of state law,” 350 U. S., at 216, and further that “[n]o injunction is sought against a state official,” id., at 217. The opinion is barren of any suggestion that any inroads on Stefanelli were intended.
It is no answer to say, as the Court of Appeals did, that this petitioner “is not being enjoined in his capacity as a state official, but as a witness invited to observe illegal activity by federal agents,” 293 F. 2d, at 369. For it is abundantly clear that the petitioner was present at these occurrences precisely and only because of his official connection with the Waterfront Commission. The District Court expressly found that it was “[t]he Waterfront Commission,” not petitioner, which “had been informed of [respondent] Bolger’s detention,” 189 F. Supp., at 244, and that petitioner “was present at the questioning [of Bolger] as a representative of the Waterfront Commission,” id., at 255.
Nor can the injunctive relief against this petitioner find justification in the rationale that it was required in order to make the injunction against the federal officers effective. Such relief as to him must stand on its own bottom. We need not decide whether petitioner’s status as a state official might be ignored had it been shown that he had misconducted himself in this affair, that he had been utilized by the federal officials as a means of shielding *400their own alleged illegal conduct, or that he had received the evidence in direct violation of a federal court order. Here the District Court found that petitioner was not a factor in the federal investigation11 and that his presence there was simply “the result of the commendable cooperation between the Customs Service and the Commission who were both concerned with law enforcement on the waterfront.” 189 F. Supp., at 255.12 On this record the upshot of the matter is that, insofar as this state official is concerned, nothing in Rea justifies disregard of the teachings of Stefanelli. Nor is the vitality of the principles on which the latter case rested sapped by this Court’s decision in Mapp v. Ohio, 367 U. S. 643, overruling Wolf v. Colorado, 338 U. S. 25, which had refused to extend to the States the exclusionary rule of Weeks v. United States, 232 U. S. 383. For in denying the injunctive relief there sought Stefanelli expressly laid to one side any possible impact of Wolf. 342 U. S., at 119-120.
The withholding of injunctive relief against this state official does not deprive respondent of the opportunity for federal correction of any denial of federal constitutional rights in the state proceedings. To the extent that such rights have been violated, cf., e. g., Mapp v. Ohio, *401supra, he may raise the objection in the state courts and then seek review in this Court of an adverse determination by the New York Court of Appeals. To permit such claims to be litigated collaterally, as is sought here, would in effect frustrate the deep-seated federal policy against piecemeal review.
To the extent that respondent’s claims involve infractions merely of the Federal Criminal Rules, we need not decide whether an adverse state determination upon such claims would be reversible here. Cf., e. g., Gallegos v. Nebraska, 342 U. S. 55. For in any event we do not think that an injunction against this state official is justified in the circumstances of this case. Assuming that such relief was properly granted here as to the federal officials in the exercise of federal-court supervisory power over them, we consider that a supplementing injunction should not issue against a state official, at least where, as here, there is no evidence of a purpose to avoid federal requirements and the information has not been acquired by the state official in violation of a federal court order. Such direct intrusion in state processes does not comport with proper federal-state relationships.
We conclude ■ that the injunction as to this petitioner should not have been granted, and that the judgment of the Court of Appeals must accordingly be
Reversed.
See De Veau v. Braisted, 363 U. S. 144.
The other Waterfront Commission detective, Machry, had apparently left the scene at an earlier stage. He was not joined as a defendant in the present action.
Respondent also instituted a second federal action against the Waterfront Commission and its members, seeking to enjoin the use of the same evidence in the license-revocation proceeding. That suit was dismissed by the District Court and is not involved here.
The District Court held that respondent’s arrest and the search of his automobile by the- federal agents were not illegal, and also denied return of any of the property seized at respondent’s home on the premise that it was contraband. Neither of those determinations is before us.
Rule 41 (a): “Authority to Issue Warrant. A search warrant authorized by this rule may be issued by a judge of the United States or of a state, commonwealth or territorial court of record or by a United States commissioner within the district wherein the property sought is located.”
Rule 5 (a): “Appearance before the Commissioner. An officer making an arrest under a warrant issued upon a complaint or any person making an arrest without a warrant shall take the arrested person without unnecessary delay before the nearest available commissioner or before any other nearby officer empowered to commit persons charged with offenses against the laws of the United States. When a person arrested without a warrant is brought before a commissioner or other officer, a complaint shall be filed forthwith.” See McNabb v. United States, 318 U. S. 332.
It should be noted that respondent did not allege in his complaint that the matter in controversy exceeded the sum or value of $10,000, or that diversity of citizenship existed. See 28 U. S. C. §§ 1331, 1332. Nor did he allege that the District Court had jurisdiction to enjoin petitioner incidental to its supervisory power over federal law enforcement agencies, cf. Rea v. United States, 350 U. S. 214, 217, or that 28 U. S. C. § 1343 conferred jurisdiction. But, in view of our determination that equitable power should not have been exercised with respect to this petitioner, it is not necessary to resolve the ques*397tions whether the complaint stated a cause of action as to him or whether federal jurisdiction existed or was adequately invoked. See Stefanelli v. Minard, 342 U. S. 117, 120.
Rule 41 (e) provides that the material suppressed “shall not be admissible in evidence at any hearing or trial.”
The Court of Appeals was also disposed to think that the propriety of the District Court’s injunction was not affected by this Court’s decision in Mapp v. Ohio, 367 U. S. 643, which came down after this ease had left the District Court.
None of the federal officers involved in this action has sought review in this Court. And for reasons stated in this opinion there is otherwise no need for determining the propriety of the injunction as to them in order to dispose of the case before us.
“In the case at bar the wrongful activities were all those of federal officers and were conducted or directed by them. All that was done during the period of unlawful detention, and particularly the taking of the incriminating statement from Bolger, was being done on behalf of the United States. Cleary was merely a witness to them.” 189 F. Supp., at 256.
We attach no significance to the District Court’s remark that petitioner’s “presence might have been an additional inducement to Bolger to answer questions more freely” (189 F. Supp., at 255) because Bolger, when originally picked up by the'federal officers, had exhibited concern about the possible effect of his transgressions on his longshoreman’s license. The record is barren of any evidence indicating that petitioner was brought into the situation for the purpose of intimidating Bolger or that he in fact did so.