delivered the opinion of the court.

In a joint indictment the plaintiff in error, Gouled, one Vaughan, an officer of the United States Army, and a third, an attorney at law, were charged, in the first count, with being parties to a conspiracy to defraud the United States, in violation of § 37 of the Federal Criminal Code, and, in the second count, with having used the mails to[*303] promote a scheme to defraud the United States, in violation of § 215 of that Code. Vaughan pleaded guilty, the attorney was acquitted, and Gouled, whom we shall refer to as the defendant, was convicted, and thereupon prosecuted error from the Circuit Court of Appeals, which certifies to this court six questions which we are to consider.

Of these questions, the first two relate to the admission in evidence of a paper surreptitiously, taken from the office of the defendant by one acting under direction of officers of the Intelligence Department of the Army of the United States, and the remaining four relate to papers taken from defendant’s office, under two search warrants, issued pursuant to the Act of June 15, 1917, c. 30, 40 Stat. 217, 228. It was objected on the trial, and is here insisted, that it was error to admit these papers in evidence because possession of them was obtained by violating the rights secured to the defendant by the Fourth and Fifth Amendments to the Constitution of the United States.

The Fourth Amendment reads:

• “The right of the people to be secure in their persons, houses, papers -and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause, supported by oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.”

The part of the Fifth Amendment here involved reads:

“No person . . . shall be compelled in any criminal case to be a witness against, himself.”

It would not be possible to add to thé emphasis with which the framers of our Constitution' and this court (in Boyd v. United States, 116 U. S. 616, in Weeks v. United States, 232 U. S. 383, and in Silverthorne Lumber Co. v. United States, 251 U. S. 385) have declared the importance to political liberty and to the welfare of our country of the due observance of the. rights guaranteed under the Consti[*304] tution by "these two Amendments. The effect of the decisions cited is: that such rights are declared to be indispensable to the “full enjoyment of personal security, personal liberty and private property”; that they are to be regarded as of the very essence of constitutional liberty; and that the guaranty of them is as important and as imperative as are the guaranties of the other fundamental rights of the individual citizen, — the right, to trial by jury, to the writ of habeas corpus and to due process of law. It has been repeatedly decided that these Amendments should receive a liberal construction, so as to prevent stealthy encroachment upon or “gradual depreciation” of the rights secured by them, by imperceptible practice of courts or by well-intentioned but mistakenly over-zealous executive officers.

In the spirit of these decisions we must deal with the questions before us.

The facts derived from the certificate, • essential to be considered, in answering the first two questions, are: that in January, 1918, it was suspected that the defendant, Gouled, and Vaughan were conspiring to defraud the Government through contracts with it for clothing and equipment; that one Cohen, a private in the Army, attached to the Intelligence Department, and a business acquaintance of defendant Gouled, under direction of his superior officers, pretending to make a friendly call upon the defendant, gained admission to his office and, in his absence, without warrant of any character, seized and carried away sevéral documents; that one of these papers, described as “of evidential value only” and belonging to Gouled, was subsequently delivered to the United States District Attorney, and was by him introduced in evidence over the objection of the defendant that possession of it was obtained by a violation of the Fourth or Fifth Amendment to the Constitution; and that the defendant did not know that Cohen had earned away any of his papers until[*305] he appeared on the witness stand and detailed the facts with respect thereto as we have stated them, when, necessarily, objection was first made to the admission of the paper in evidence.

• Out of these facts arise the first two questions, both relating to the paper thus seized. The first of these, is:

“Is the secret taking or abstraction, without force, by a. representative of any branch or subdivision of the Government of the United States, of a paper writing of evidential value only belonging to one suspected of crime and from the house or office of such person, — a violation of the 4th amendment?”

The.ground on which the trial court overruled the objection to this paper is not stated, but from the certificate and the argument we must infer that it was admitted either because it appeared that the possession of it was obtained without the use of force or illegal coercion, or because the objection to it came too late.

The objection was not too late, for, coming as it did promptly upon the first notice the defendant had that the Government was in possession of the paper, the rule of practice relied upon, that such an objection will not be entertained unless made before trial, was obviously inapplicable.

The prohibition of the Fourth Amendment is against all unreasonable seárches and seizures and if for a Government officer to obtain entrance to a man’s house or office by force or by an illegal threat or show of force, amounting to coercion, and then to search for and seize his private papers would be an unreasonable and. therefore a prohibited search and seizure, as it certainly would be, it is impossible to successfully contend that a like search and seizure would be a reasonable one if only admission were obtained by stealth instead of by force or coercion. The security and privacy of the home or office ancLof the papers of the owner would be as much invaded and the search and[*306] seizure would be as much against his will in the one case as in the other, and it must therefore be regarded as equally in violation of his constitutional rights.

Without discussing them, we cannot doubt that such decisions as there are in conflict with this conclusion are unsound, and that, whether entrance to the home or office of a person suspected of crime be obtained by a representative of any branch or subdivision of the Government of the United States by stealth, or through social acquaintance, or in the guise of a business call, and whether the owner be present or not when he enters, any search and seizure subsequently and secretly made in his absence, falls within the scope of the prohibition of the Fourth Amendment.,, and therefore the answer to the first question must be in the affirmative.

The second question reads:

“Is the admission of such paper in evidence against the same person when indicted for crime a violation of the bth amendment? ”

Upon authority of the Boyd Case, supra, this second question must also be answered in the affirmative. In practice the result is the same to one accused of crime, whether he be obliged to supply evidence against himself or whether such evidence be obtained by an illegal search of his premises and seizure of his private papers. In either case he is the unwilling source of the evidence, and the Fifth Amendment forbids that he shall be compelled to be a witness against himself in a criminal case.

The remaining four questions relate' to three other papers which were admitted in evidence on the trial over the same constitutional objections as were interposed to the admission of the first paper. One was an unexecuted form of contract between the defendant and one Lavinsky, another was a written contract, signed by the defendant and one Steinthal, and the third was a bill for[*307] disbursements and professional services rendered by the attorney at law to the defendant Gouled.

Of these' papers, the first was seized in defendant’s office under a search warrant, dated June 17, and the other two under a like warrant dated July 22, 1918,-each of which was issued by a United States Commissioner on the affidavit of an agent of the Department of Justice. It is certified that it was averred in the first affidavit that there were in Gouled’s office “certain property, to wit: certain contracts of the said Felix Gouled with S. Lavihsky [which] were used as a means of committing a felony, to wit: ... as means for the bribery of a certain office? of the United States.” It is also certified that the second, affidavit declared that Gouled had at his office “certain letters, papers, documents and writings which ... relate to, concern and have been used in the commission of a felony, to wit: -a conspiracy to defraud the United States.” Neither the affidavits nor the warrants are given in full in the certificate, but no exception was taken to the sufficiency of either.

- After the seizure of the papers, a joint indictment was returned; as stated, against Gouled, Vaughan and the attorney, and before trial a motion,was made by Gouled, for a return of the papers seized under the search warrants, which was denied, and when the motion was renewed at the trial, but before any evidence was introduced, it was again , denied. The denial of this motion is not assigned as error.

The contract of the defendant with Steinthal, which-was seized under the warrant, was not offered in evidence ~but a duplicate original, .obtained from Steinthal, was admitted over the objection that the possession of the seized original must have suggested the existence and the obtaining of the counterpart, and that therefore the use of it in evidence would violate the rights of the defendant under the Fourth or Fifth Amendment. Silverthorne [*308] Lumber Co. v. United States, 251 U. S. 385. The unsigned form of contract and the attorney’s bill were offered and also admitted over the same constitutional objection. There is no statement in the certificate of the contents of these papers, but it is said of them only, that they belonged to Gouled, that they were without pecuniary value and that they- constituted evidence “more or less .injurious to” the defendant.

It is apparent from this statement that to answer the remaining four 'questions involves a consideration of the applicable law of search warrants.

The wording of the Fourth Amendment implies that search warrants were in familiar use when the Constitution was adopted and, plainly, that when issued “upon probable cause, supported by óáth or affirmation,' and particularly describing'the place to be searched, and the "persons or things to be seized,” searches, and seizures made under them, are to be regarded as not-unreasonable, and therefore not prohibited by the Amendment. Searches and seizures are as constitutional under the Amendment when made under valid search warrants as they áre unconstitutional,' because unreasonable,--when máde without them, — the .permission of the. Amendment has the same constitutional 'warrant as the prohibition has, ánd the definition of the former restrains the scope of the latter. All of this is abundantly recognized in the opinions of the Boyd and Weeks Cases, supra, in which it is pointed out that at the time the Constitution was adopted stolen of forfeited property, or property liable to duties and concealed to avoid payment of them, excisable articles and books required by law to be kept with respect to them,' counterfeit coin, burglars’ tools and weapons, impleráents 'of gambling “and many other things of like character,” might be seárched for in home of office and if found might be seized, under search warrants, lawfully applied for, issued and executed.

[*309] Although search warrants have thus been used in many cases ever since the adoption of the Constitution, and although their use has been extended from time to .time to meet new cases within the old rules, nevertheless it is clear that, at common law and as the result of the Boyd and Weeks Cases, supra, they may not be used as a means of gaming access to a man’s' house or office and papers solely for the purpose of making search to secure evidence to be used against him in a criminal or penal proceeding, but that they may be resorted to only when a primary right to such search and seizure may be found in the interest which the public or the complainant may have in the property to be seized, or in the right to the possession of it, or when a Valid exercise of the police power renders possession of the property by- the accused unlawful and provides that it may be taken. Boyd Case, pp. 623, 624.

There is no special sanctity in papers, as distinguished from other forms of property, to render them immune from search and seizure, if only they fall within the scope of the principles of the cases in which other property may be seized, and if they be adequately described in the affidavit and warrant. Stolen or forged papers have been so seized, Langdon v. People, 133 Illinois, 382, and lottery tickets, under a statute prohibiting their possession with intent to sell them, Commonwealth v. Dana, 2 Mete. 329, and we cannot doubt that contracts may be so used as instruments or agencies for perpetrating frauds upon the Government as to give the public an interest in them which would justify the search for and seizure of them, under a properly issued search warrant, for the purpose of preventing further frauds.

With these principles of law in mind, we come to the remaining questions.

The third question.reads: “Are papers of no pecuniary value ,but possessing evidential value against persons presently suspected and subsequently indicted under[*310] Sections 37 and 215 of the United States Criminal Code, when' taken under search warrants issued pursuant to the Act of June 15, 1917, from the house or office of the person so suspected, — seized and taken in violation of the 4th Amendment? ”

That the papers involved are of no pecuniary value is of no significance. Many papers, having no pecuniary value to others, are of the greatest possible value to the owners and are property of a most important character (Boyd Case, supra, pp. 627, 628), and since those here involved possessed “evidential value ” against the defendant, we must assume that they were relevant to the issue..

Restraining the questions to the papers described, and first as to the unexecuted form of contract with Lavinsky, a stranger to the indictment. While the contents of this paper are not given, it is impossible to see how the Government could have such an interest in such a paper that under the principles of law stated it would have the right to take it into its possession to prevent injury to the public from its use. The Government could desire its possession only to use it as evidence against the defendant and to search for and seize it for such purpose was unlawful.

Likewise the public could be interested in the bill of the attorney for legal services only to the extent that it might be used as evidence and the seizure of this also was unlawful. '

As to the contract with Steinthal, also a stranger to the indictment. It is not difficult, as we have said, to imagine, how an executed written contract might be an important agency or instrumentality in the bribing of a public servant and in perpetrating frauds upon the Government so that it would have a legitimate and important interest in seizing such a paper in order to prevent further frauds, but the facts necessary to give this contract such a character do not appear in the certificate. On the con[*311] trary, -this third question recites that the papers are all of no pecuniary, but are of evidential, value, and in the sixth question it is recited that they are “of evidential value only,” so that it is impossible to say; on the record before us, that the Government had any interest in it other than as evidence against the accused, and therefore as to all three papers the answer to the question must be in the affirmative.

The fourth question reads: “If such papers so taken are admitted in evidence against the person from whose house or office they were taken, such person being then on trial for the crime of which he was accused in the affidavit for warrant, — is such admission in evidence a violation of the 5th amendment? ”

The same papers being involved, the answer to this question must be in the affirmative for, they having been seized in an unconstitutional search, to permit them to be used in evidence would be, in effect, as ruled in the Boyd Case, to compel the. defendant to become a witness against himself.

The fifth question reads: “If in the affidavit for search warrant under Act of June 15, 1917, the party whose premises are to be searched be charged with one crime and property be taken under the warrant issued thereon, —can such property so seized be introduced in evidence against said party when on trial for a different offence? ”

It has never been required that a criminal prosecution should be pending against a person in order to justify search for and seizure of his property under a proper warrant, if a case of crime having been committed and of probable cause is made out sufficient to satisfy the law and the officer having authority to issue it, and we see no reason why property seized under a valid search warrant, when thus lawfully obtained by the Government, may not be used in the prosecution of a suspected person for a crime other than that which may have been described[*312] in the affidavit as having been committed by him. The question assumes that the property seized was obtained on a search warrant, sufficient in form to satisfy the law, and if the papers to which the question refers had been of a character to be thus obtained, lawfully, it would have been competent to use then! to prove any crime against the accused as to which they constituted relevant evidence.

The sixth question reads: “If papers of evidential value only be seized under a search warrant and t^e party from whose house or office they are taken be indicted;— if he then move before trial for the return of said papers and said motion is denied — is the court at trial bound in law to inquire as to. the origin of or method of procuring said papers when they are offered in. evidence against the party so indicted? ”

The papers being of “evidential value only” and having been unlawfully seized, this question really is, whether, it having been decided on a motion before trial that they should not be returned to the defendant, the trial court, when objection was made to their use on the trial, was' bound to again inquire as to the unconstitutional origin of thé possession of them. It is'plain that the trial court acted upon the rule, widely adopted, that courts in criminal trials will not pause to. determine how the possession of evidence tendered has been obtained. While tliis is a rule; of great practical importance, yet, after all, it is only a rule of procedure, and therefore it is not to be applied as a hard and fast formula to every case, regardless of its.special circumstances. We think rather that it is a rule to be used to secure the ends of justice under the circumstances presented by each case, and -where, in the progress of a trial, it becomes propable that there has been an unconstitutional seizure of papers, it is the. duty of the trial court to entertain an objection to their admission or a motion for their exclusion and to consider[*313] and decide the question as then presented; even where a motion to return the papers may have been denied before trial. A rule, of practice must not be allowed for any technical reason to prevail over a constitutional right.

In the case we are considering the certificate shows that a motion to return the papers, seized under the search warrants, was made before the trial, and was denied, and that, on the trial of the case before another judge, this ruling was treated as conclusive, although, as we have seen, in the progress of the trial it must have become. apparent that the papers had been unconstitutionally seized. The constitutional objection having been renewed,.,. under the circumstances, the court should have inquired as to the origin of the possession of the papers when they were offered in evidence against the defendant.

Each question is answered, Yes.