(dissenting).
I
I do not find any search or seizure in th® facts of this case.
What I find in the record is the following: A Senate Committee was investigating interstate crime. It not only had the power but also had a duty to do so. Charles E. Nelson was a witness duly subpoenaed and sworn. He was questioned about the activities of several concerns, principally one known as Robert Nowland Associates, it later developing that the Committee had information that he had received some $180,000 from this concern in four years. The witness repeatedly asserted his sincere purpose to cooperate with the Committee. He volunteered the suggestion that his books were a more accurate evidence of figures inquired about, and later he was rather insistent to that effect. He readily concurred in the suggestion that he go fetch the books, which he said were at home. This witness was obviously either deaf, extremely nervous, or stalling. He was warned several times in language similar to that which a trial judge ordinarily directs to a recalcitrant witness. Once in the middle of the hearing and again at the end of it he was asked whether a member of the staff could go with him to get a then-current 1951 book. He readily agreed, drove the official to his home, got out the records now the subject of this dispute, gave them to the official, and drove him back to the Capitol.
At no point did Nelson offer any objection either to pertinency or of privilege.
Clear understanding requires a little more specific statement of the facts than the foregoing summary. Nelson parried questions. He was warned that he was a witness and must tell the truth. He repeatedly insisted that he was trying to do so, to cooperate. He was reminded that his income tax return for 1948 showed $49,936 as receipts from Nowland Associates. Asked where he “put down” what he received, Nelson said he listed it in a book. He was asked where the book was and replied, “They are kept in separate years, and I don’t know — I will try to locate them for you, if it will be of any help.” I interject that this is the critical point in all that followed. This was a clear, unsolicited offer by the witness to locate and furnish more specific, more accurate information. Nelson repeatedly denied that he knew certain facts about Nowland and constantly asserted his wish to tell whatever he knew; for example, “Believe me, as much as I would like to, I can not. I would love to, if I really *519knew the facts — I would tell you in a minute.” He was asked what he had received from Nowland in the then-current year, 1951. He replied “I do not have any idea right now” and “I have to go back to whatever records we keep.” Asked where the records were, he said they were at home. Then the following occurred:
“Mr. Rice. And if we were to suggest that a staff member might like to accompany you out to the little red book, can he see that?
“Mr. Nelson. It would be all right with me.”
After a long interrogation, during which Nelson repeatedly made reference to the necessity for looking at books (bank books, etc.), the presiding Senator said:
“Senator Hunt. Mr. Nelson, we will have a staff member accompany you out to your home and if you will turn over to him your account book, the little red book you spoke of, he will see that you get a receipt for it and the committee will return it to you at the very earliest date, so as not to inconvenience you any.
“You are now excused, Mr. Nelson.
“Mr. Nelson. I am afraid I do not understand what it is you want me to do.
“Senator Hunt. Well, we will have a member of the staff — you tell me if you are not hearing- — go with you out to your home and you turn over to him a statement of your net worth together with your little account book that you spoke of as the little red book, where you keep your ‘ins’ and ‘outs’, as you said. In addition to that, the subpoena that you are now testifying under will hold until such time as the committee releases the subpoena.”
I interject again. My brethren say that the promise of the Committee to return the papers “at the very earliest date” bears vitally upon the search and seizure question. I do not see the perti-nency of the promise to search and seizure, because Nelson, having first volunteered to get the books, had agreed to get them before this promise was made.
The account of the visit to Nelson’s home is as follows in the affidavit of the staff member and is uncontradicted:
“* * * pursuant to his instructions, affiant immediately accompanied Charles E. Nelson in the latter’s automobile to his home in Prince Georges County, Maryland; that on arriving at the Charles E. Nelson home, affiant and Nelson went to an office which Nelson had there; that on a desk in said office there was a paper with what appeared to be several names thereon, and Mr. Nelson took the paper from the desk and put it in his pocket; affiant asked Charles E. Nelson where the 1951 ‘little red book’ was, and he stated that it was not all together as yet but that he had something in the office which might serve as an indication of what his business was, and Nelson then went to a file cabinet and pulled out the bottom drawer; affiant saw about ten large envelopes, apparently filled with papers, and also two or three little bound books; Nelson picked up one of these books from the drawer and showed it to affiant; af-fiant examined the book and saw that it was a 1942 ledger concerning lottery and numbers operations in which Charles E. Nelson was involved; Nelson then told me that I could look in the drawer, see whatever I liked and take out whatever I wished, and that if I cared to take these records with me it would be perfectly all right. I asked Nelson if we might have the whole file and he said he would be glad to let me have anything I would like to have. I noticed, and Nelson stated to me, that there were no 1951 records among these envelopes, records and papers, and the latest of the data covered the year 1950, while the earliest year covered was the year 1940; affiant also observed that all *520of these records related to lottery and numbers operations of Charles E. Nelson during that period; that Charles E. Nelson helped affiant tie the records, envelopes and data together and then helped affiant take them out and put them in the Nelson car and then he drove affiant and the records back to Washington, D. C.”
It seems pertinent to me that, as a matter of fact, Nelson did not claim in his motion to suppress the evidence in the District Court that the obtaining of this material from him by the Committee was illegal; he claimed that the obtaining of the material by the United States Attorney from the Committee was an illegal search and seizure and violated his privilege against self-incrimination. In his affidavit in support of that motion, Nelson asserted that he “turned over to a Committee of the United States Senate” these books, etc. His point was that he had a “definite assurance” that they would be returned to him and that “no permission was ever given by him to said Committee to permit any other persons” to examine the documents. To me this is a clear statement that the possession of the documents by the Committee itself was deemed by Nelson to have been with his permission, even at so late a date as the time when he was moving for suppression of the evidence.
At the argument on the motion counsel for Nelson included the contention that the acquisition of the documents by the Committee was by an illegal search and seizure. The Government protested that argument. When the documents were proffered at the trial Nelson’s counsel objected on the ground that they were obtained by a fraud, that is, the promise given Nelson by the Committee that they would be returned to him; and also on the ground that they were not admissible under the statute.1 I do not find in the record of the trial, except in so far as the argument on the motion was incorporated in it, any contention respecting search and seizure by the Committee. In the briefs filed in this court the point seems to be hinted at, but it is interwoven in the argument that the transfer of the papers from the Committee to the United States Attorney was a “trickery” and for that reason an illegal search and seizure; certainly the point that the Committee’s acquisition of the documents was a search and seizure was not stressed. Able counsel represented these defendants throughout. Their lack of enthusiasm for the contention could not have been inadvertent. I think their estimate of its worth was correct.
I think we ought not to spin out a search and seizure where none exists in fact. No one, I think, is more emphatic than I am in respect to the constitutional protections of privacy both of person and of property. But we ought not to transmute invitation into invasion, admonitions normal in judicial proceedings into illegal compulsions, absence of objection into paralysis, proffers into searches, or acceptances into seizures; unless the facts compel us to do so.
Nelson was a witness. A witness must (a) answer questions and (b) tell the truth. If a witness does not answer questions he can be punished for contempt. If a witness does not tell the truth he can be punished for perjury. This is not merely coercion but is compulsion. Such compulsion is an essential and perfectly sound feature of the judicial process. It is quite customary for a court to warn a witness that he must tell the truth; the same should apply to other tribunals authorized to take testimony under oath. A witness may refuse to answer if (a) the question is not pertinent to the inquiry or (b) the answer would tend to incriminate him. But he must assert those reasons. If he does not assert them they are not available later. No objections to questions or to answering were made by Nelson before the Committee. Nelson’s status, therefore, was that of a witness under compulsion to answer questions *521unless he interposed a valid objection, and he interposed none.
It is certainly clear that a statute compels witnesses before congressional committees to answer questions, under pain of fine and imprisonment, and the statute has been applied in many cases, from In re Chapman 2 to United States v. Bryan.3 If it be agreed that Nelson’s books could have been obtained by the Committee by an “orderly taking under compulsion of process,”4 to wit, a subpoena duces tecum, the question in the case at bar becomes merely whether the formal execution of a subpoena is essential when a willing witness proffers and then delivers documents. The question is not whether the Committee ought to go to some other authority and get a subpoena; it is whether the Committee itself, having full subpoena powers, should be compelled to issue one upon a willing witness. To say that the formality is essential in such circumstances is, in my judgment, to magnify a technicality beyond all relation to reality.
My brethren would equate a representative of an investigating committee accompanying a witness to his home to obtain proffered evidence, with a police officer demanding entrance to a private home for a search without a warrant. I cannot equate them. They seem to me to be wholly different matters. The Committee had power to issue process for the compulsory production of the books. The idea was not that of the officer. It germinated in the very presence of the Committee, instigated by Nelson himself. Nelson was not in his home; he was on the witness stand, under subpoena and sworn. The action was not that of the officer on his own; it was directed by the tribunal which had power to compel it.
What would have made a difference, in my view, would have been an objection by Nelson. Then what was done would have instantly been restricted to the limitations upon and the formal requirements of official process.
My brethren say that Nelson was coerced. But I search the record in vain to find any coercion except that which arose from the fact that Nelson was a witness. The officer did not suddenly appear before Nelson and demand something. He was sent by the Committee pursuant to a request made by the Committee upon Nelson and acquiesced in by him.
The decision in the Judd case5 is not pertinent here, in my view, because the facts there were totally different. Judd was a prisoner under arrest and in jail when his alleged consent was given; consent for a search was sought by uniformed police officers; there was an actual search in fact; the search was of Judd’s residence; Judd was taken to his residence in handcuffs at two o’clock in the morning; no claim was made that assent to a search was given when the apartment was reached; it was not disputed that Judd’s wife, who was in the apartment, protested the search. The question in the case was whether a consent given under such circumstances was a voluntary consent.
My brethren make reference to the facts that Nelson was not warned ahead of time that he need not answer incriminating inquiries and that he did not have counsel present. There is no rule of law that a witness must be warned 6 *522or that he have counsel during his testifying.
Mr. Justice Jackson phrased my thought upon this case when he wrote, in Stein v. New York:7
“We are' not willing to discredit constitutional doctrines for protection of the innocent by making of them mere technical loopholes for the escape of the guilty. The petitioners have had fair trial and fair review. The people of the State are also entitled to the due process of law.”
If there was no illegal search and seizure the documents were admissible against all the defendants without further consideration except as to Nelson himself. I would agree with my brethren that, if the documents were obtained from Nelson by the Committee by an unconstitutional search and seizure, they should have been returned to him and therefore were not usable as evidence against anybody, in accordance with my understanding of the McDonald case.8 As to Nelson himself, I must consider the effect of Section 3486 of Title 18 of the United States Code.
II
As to the statute9 I think it was error to admit the documents against Nelson. While they did not constitute “testimony” they did constitute evidence given by Nelson while he was a witness before the Committee. But I do not think this error constituted reversible error. There was more than ample other evidence to establish Nelson’s guilt; evidence of employees, participants in the numbers game, etc. Some twenty witnesses who said they were employees of Nelson, or who said they were otherwise engaged in the numbers operation, testified. They all testified from personal knowledge. His guilt was unquestionably established beyond a reasonable doubt by evidence not connected with these records. No contradictory evidence was presented. The only attacks made on credibility were by cross examination. The documents here in dispute were at best cumulative to the direct testimony of the witnesses.
Whether a “lead” to any of this evidence was obtained from the documents is immaterial to consideration of the applicability of the statute. It was not established that the documents supplied such leads, but in any event, so far as the statute is concerned, the use of “leads” from testimony given by a witness is not prohibited. This is the rule of Counselman v. Hitchcock,10 never overruled. An inquiry as to “leads” becomes pertinent when a constitutional privilege is asserted and the witness thereafter compelled to answer. Nelson asserted no such privilege in response to inquiry about the records.
Where an error is made in the admission of evidence by the trial court, the appellate court must exercise a careful judgment in determining whether it will or will not reverse. The rule11 says that any error “which does not affect substantial rights” shall be disregarded. In Kotteakos v. United States12 the Supreme Court told us that “If, when all is said and done, the conviction is sure that the error did not influence the jury, or had but very slight effect, the verdict and the judgment should stand * *523In Krulewitch v. United States13 the Court said that “if upon consideration of the record the court is left in grave doubt as to whether the error had substantial influence in bringing about a verdict” we should reverse. We had the problem in Campbell v. United States.14
Applying the standard thus laid down, it seems clear to me that in view of the mass of direct testimony the error of admitting these documents against Nelson could have had but very slight, if any, effect upon the verdict. I do not reach this conclusion upon a delicate balance or upon any appraisal of the evidence. I reach it because of what seems to me to be overwhelming and certain.
III
Taking the phases of the case in the order in which the court has considered them, I do not reach the question whether the action of the District Court, denying the motion to return the disputed documents and to suppress them as evidence, was res judicata. I intimate no opinion one way or the other on that point. I point out, however, that, as the court itself says, the present decision is in conflict with the Second Circuit in United States v. Poller 15 and with the Third Circuit in In re Sana Laboratories;16 and, I add, with the language of Mr. Justice Brandeis in Cogen v. United States.17 I also call attention to the fact that no objection was registered to the ruling by the trial court at the time of trial that the ruling on the motion was res judicata the point.
I would affirm the judgments.
. 18 U.S.C. § 3486.
. 1897, 166 U.S. 661, 17 S.Ct. 677, 41 L.Ed. 1154.
. 1950, 339 U.S. 323, 70 S.Ct. 724, 94 L.Ed. 884.
. United States v. Morton Salt Co., 1950, 338 U.S. 632, 652, 70 S.Ct. 357, 368, 94 L.Ed. 401.
. Judd v. United States, 1951, 89 U.S.App.D.C. 64, 190 F.2d 649.
. Bart v. United States, 1952, 91 U.S.App. D.C. 370, 203 F.2d 45, 49; Alford v. United States, 1931, 282 U.S. 687, 694, 51 S.Ct. 218, 75 L.Ed. 624; United States v. Block, 2 Cir., 1937, 88 F.2d 618, certiorari denied, 1937, 301 U.S. 690, 57 S.Ct. 793, 81 L.Ed. 1347; Pulford v. United States, 6 Cir., 1946, 155 F.2d 944; 8 Wigmore, Evidence § 2269 (3d ed. 1940).
. 346 U.S. 156, 73 S.Ct. 1077.
. McDonald v. United States, 1948, 335 U.S. 451, 69 S.Ct. 191, 93 L.Ed. 153.
. In pertinent part Section 3486 of Title 18 provides: “No testimony given by a witness * * * before any committee of either House * * * shall be used as evidence in any criminal proceeding against him in any court, except in a prosecution for perjury * *
. 1892, 142 U.S. 547, 35 L.Ed. 1110, 12 S.Ct. 196.
. Fed.R.Crim.P. 52(a), 18 U.S.C.
. 1946, 328 U.S. 750, 764, 66 S.Ct. 1239, 90 L.Ed. 1557.
. 1949, 336 U.S. 440, 445, 69 S.Ct. 716, 93 L.Ed. 790.
. 1949, 85 U.S.App.D.C. 133, 176 F.2d 45.
. 1930, 43 F.2d 911, 74 A.L.R. 1382.
. 1940, 115 F.2d 717, certiorari denied, 1941, 312 U.S. 688, 61 S.Ct. 615, 85 L.Ed. 1125.
. 1929, 278 U.S. 221, 225, 49 S.Ct. 118, 73 L.Ed. 275.