Per Curiam.
In Davis v. United States, post, p. 927, we today denied the- petition for certiorari. The sole question raised there (but not passed upon by the Court of Appeals because not necessary to its disposition) involved petitioners’ claim that conferences between petitioners and their counsel were surreptitiously overheard and intercepted by law enforcement officials through concealed monitorial devices built into the jail where petitioners were being held for federal authorities. The Solicitor General did not deny the existence of the devices but said that there were no recordings of the conversations in question. He pointed out that since the case has been remanded by the Court of Appeals for a new trial on other grounds, a full exploration of this question could be made on retrial. In the light of these representations we denied the petition for certiorari so that the question might be fully explored at the new trial, as suggested by the Solicitor General.
In the instant case, Black v. United States, the petition for rehearing now raises a similar question and while Davis v. United States, supra, is not controlling, its relation is obvious. In Black the Solicitor General advised the Court voluntarily on May 24, 1966, after the petition for certiorari had been denied, 384 U. S. 927, but before an application for rehearing had been filed, that agents of the Federal Bureau of Investigation, in a matter unrelated to this case, on February 7, 1963, installed a listening device in petitioner’s hotel suite in Washington, D. C. The device monitored and taped conversations held in the hotel suite during the period the offense was being investigated and beginning some two months before and continuing until about one month after the evidence in this case was presented to the Grand Jury. During that period, “the monitoring agents,” the Solicitor General advised, “overheard, among other conversations, exchanges between petitioner and the attorney who was then representing him [Black]” in this case. In a supplemental memorandum filed July 13, 1966, the Solicitor General, in response to an inquiry by the Court, stated that the recordings of such interceptions had been erased from the tapes but that notes summarizing and sometimes quoting the conversations intercepted were available, and that reports and memoranda concerning the same had been made. “Neither the reports nor the memoranda,” he reported, “were seen by attorneys of the Tax Division responsible for the prosecution of” this case until January 1964, when in preparing for trial they were included in material transmitted to them; the reports and memo-randa of the intercepted conversations were examined by the Tax Division attorneys and retained by them until April 15, 1964, when petitioner’s trial began; and the attorneys never realized until April 21, 1966, that any conversations between Black and his attorney had been overheard and included in the transcriptions.
The Solicitor General advised further that the “Tax Division attorneys found nothing in the F. B. I. reports or memoranda which they considered relevant to the tax evasion case.” He suggests that the judgment be vacated and remanded to the District Court in which the “relevant materials would be produced and the court would determine, upon an adversary hearing, whether petitioner’s conviction should stand.” We have sometimes used this technique in federal criminal cases, United States v. Shotwell Mfg. Co., 355 U. S. 233. However, its use has never been automatic. Indeed, in Remmer v. United States, 347 U. S. 227, we found it necessary, despite the hearing in the District Court, to subsequently order a new trial on the merits, 350 U. S. 377. There are other complicating factors here that were not present in Remmer. There the judge had been informed of the alleged jury tampering, but here neither the judge, the petitioner nor his counsel knew of the action of the federal agents. Moreover, the Solicitor General advises that the Tax Division attorneys did not know at the time of the trial that conversations between Black and his attorney were included in the transcriptions. In view of these facts it appears that justice'requires that a new trial be held so as to afford the petitioner an opportunity to protect himself from the use of evidence that might be otherwise inadmissible.
This Court has never been disposed to vacate convictions without adequate justification, but, under the circumstances presented by the Solicitor Ceneral in this case we believe that a new trial must be held. This will give the parties an opportunity to present the relevant evidence and permit the trial judge to decide the questions involved. It will also permit the removal of any doubt as to Black’s receiving a fair trial with full consideration being, given to the new evidence reported to us by the Solicitor General.
The petition for rehearing is therefore granted, the order denying certiorari vacated, certiorari granted, the judgment of the Court of Appeals vacated and the cause remanded to the District Court for a new trial.
Mr. Justice White and Mr. Justice Fortas took no part in the consideration or decision of this case.