after filing the above statement of facts, delivered the opinion of the court, as follows:
The motion for a peremptory order upon the witness to answer the interrogatories propounded by the railway commission has been fully argued; and every thing which could be said in its favor has been ably presented by the United States attorney, either in oral or printed arguments. In resisting the motion, counsel of the respondent have not confined themselves to a discussion of the propriety and necessity of the interrogatories, and the sufficiency of the answers given by him; but they have assailed the validity of the act creating the commission, so far as it authorizes an examination into the private affairs of the directors, officers, and employes of the Central Pacific Railroad Company, and confers the right to invoke the power of the federal courts in aid of the general investigation directed. Impressed with the gravity of the questions presented, we have given to them all the consideration in our power.
The Pacific Railway Commission, created under the act of congress of March 3, 1887, is not a judicial body; it possesses no judicial powers; it can determine no rights of the government, or of the companies whose affairs it investigates. Those rights will remain the subject oT judicial inquiry and determination as fully as though the commission had never been created; and in such inquiry its report to the president of its action will not ho even admissible as evidence of any of the matters investigated. It is a mere board of inquiry, directed to obtain information upon certain matters, and report the result of its investigations to the president, who is to lay the same before congress. In the progress of its *250investigations, and in the furtherance of them, it is in terms authorized to invoke the aid of the courts of the United States in requiring the attendance and testimony of witnesses, and the production of books, papers, and documents. And the g.ct provides that the circuit or district court of the United States, within the jurisdiction of which the inquiry of the commission is had, in case of contumacy or refusal of any person to obey a subpoena to him, may issue an order requiring such person to appear before the commissioners, and produce books and papers, and give evidence touching the matters in question.
The investigation directed is to be distinguished from the inquiries authorized upon taking the census. The constitution provides for an enumeration of the inhabitants of the states at regular periods, in order to furnish a basis for the apportionment of representatives, and, in connection with the ascertainment of the number of inhabitants, the act of congress provides for certain inquiries as to their age, birth, marriage, occupation/, and respecting some other matters of general interest', and for a refusal of ánv one to answer them a small penalty is imposed. Rev. St. § 2171. There is no attempt in such inquiries to pry into the private affairs and papers of any one, nor are the courts called upon to enforce answers to them. Similar inquiries usually accompany the taking of a census of every country, and are not deemed to encroach upon the rights of the citizen. And in addition to the' inquiries usually ac?. companying the taking of a census, there is no,doubt that congress may authorize a commission to obtain information upon any subject which, in its judgment, it may be important to possess. It may inquire into the extent of the productions of the country of every kind, natural and artificial, and seek information as to the habits, business, and even amusements of the people. But in its inquiries it is controlled by the same guards against the invasion of private rights which limit the Investigations of private parties into similar matters. In the pursuit of knowledge it cannot compel the production of the pi-ivate books and papers of the citizen for its inspection, except in the progress of judicial proceedings, or in suits instituted for that purpose, and in both cases only upon averments that its rights are in some way dependent for enforcement upon the evidence those books and papers contain.
Of all the rights of the citizen, few are of greater importance or more essential to his peace and happiness than the right of personal security, and that involves, not merely protection of his person from assault, but exemption of his private affairs, books, and papers from the inspection and scrutiny of others. Without the enjoyment of this right, all other rights would lose half their value. The law provides for the compulsory production, in the progress of judicial proceedings, or by direct suit for that purpose, of such documents as affect the interest of others, and also, in certain cases, for the seizure of criminating papers necessary for the prosecution of offenders against public justice, and only in one of these ways can they be obtained, and their contents made known, against the will of the owners.
In the recent case of Boyd v. U. S., 116 U. S. 616, 6 Sup. Ct. Rep. 524, the supreme court held that a provision of a law of congress, which *251authorized a court of the United States in revenue cases, on motion of the government attorney, to require the defendant or claimant to produce in court his private books, invoices, and papers, or that the allegations of the attorney respecting them should be taken as confessed, was unconstitutional and void as applied to suits for penalties or to establish a forfeiture of the party’s goods. The court, speaking by Mr. Justice Beadley, said:
“Any compulsory discovery by extorting the party’s oath, or compelling the production of his private books and papers, to convict him of crime or to forfeit his property, is contrary to the principles of a free government. It is abhorrent to the instincts of an Englishman; it is abhorrent to the instincts of an American. It may suit the purpose of despotic power; but it cannot abide the pure atmosphere of political liberty and personal freedom.”
The language thus used had reference, it is true, to the compulsory production of papers as a foundation for criminal proceedings, but it is applicable to any such production of the private books and papers of a party otherwise than in the course of judicial proceedings, or a direct suit for that purpose. It is the forcible intrusion into, and compulsory exposure of, one’s private affairs and papers, without judicial process, or in the course of judicial proceedings, which is contrary to the principles of a free government, and is abhorrent to the instincts of Englishmen and Americans.
In his opinion in the celebrated case of Entick v. Carrington, reported at length in 19 How. State Tr. 1029, Lord Camden said;
“Papers are the owner’s goods and chattels; they are his dearest property, and are so far from enduring a seizure that they will hardly b.ear an inspection; and though the eye cannot, by the laws of England, be guilty of a trespass, yot, where papers are removed and carried away, the secret nature of those goods will be an aggravation of the trespass, and demand more considerable damages in that respect. Where is the written law that gives any magistrate such a power? I can safely answer there is none; and therefore it is too much for us, without such authority, to pronounce a practice legal which would be subversive of all the comforts of society.”
Cpmpulsory process to produce such papers, not in a judicial proceeding, but before a commissioner of inquiry, is as subversive of “all the comforts of-society” as their seizure under the general warrant condemned in that case. The principles laid down in the opinion of Lord Camden, said the supremo court of the United States, “affect the very essence of constitutional liberty and security. They reach further than the concrete form of the case then before the court with its adventitious circumstances; they apply to all invasions on the part of the government, and its employes, of the sanctity of man’s home and the privacies of life.”
In Kilbourn v. Thompson, 103 U. S. 168, we have a decision of the supreme court of the United Slates that neither house of congress has the power to make inquiries into the private affairs of the citizen; that is, to compel exposure of such affairs. That case was this: The firm of Jay Cooke & Co. were debtors of the United States, and it was alleged that they were interested in a “real-estate pool” in the city of Washington, and that the trustee of their estate and effects had made a settlement of their interests with the associates of the firm to the disadvan*252tage and loss of numerous creditors, including the government of the United States. The house of representatives-, by a resolution reciting these facts, authorized the speaker to appoint a committee of five to inquire into the matter and history of said “real-estate pool,” and the character of the settlement, with the amount of the property involved, in which Jay Cooke & Co. were interested, and the amount paid, or to be paid, in said settlement, with power to send for persons and papers, and report to the house. The committee was appointed and organized, and proceeded to make the inquiry directed. A subpoena was issued to one Kilbourn, commanding him to appear before the committee to testify and be examined touching the matters to be inquired into, and to bring with him certain designated records, papers, and maps relating to the inquiry. Kilbourn appeared before the committee, and was asked to state the names of the five members of the real-estate pool, and w'here each resided, and he refused to answer the question, or to produce the books which had been required. The committee reported the matter to the house, and it ordered the speaker to issue his warrant directed to the sergeant-at-arms to arrest Kilbourn, and bring him before the bar of the house to answer why he should not be punished for contempt. On being brought before the house, Kilbourn persisted in his refusal to answer the question, and to produce the books and papers required. He was thereupon held to be in contempt, and committed to the custody of the sergeant-at-arms until he should signify his willingness to appear before the committee and answer the question and obey the subpoena duces tecum; and it was ordered that in the mean time the sergeant-at-arms should cause him to be confined in the common jail of the District of Columbia.. He was accordingly confined in that jail for 45 days, when he was released on habeas corpus by the chief justice of the supreme court of the District of Columbia. Upon his release he sued the speaker of the house, the members of the committee, and the sergeant-at-arms for his forcible arrest and confinement. The defendants pleaded the facts recited, to which plea the plaintiff demurred. The demurrer was overruled, and judgment ordered for the defendants. On a writ of error to the supreme court the judgment was affirmed as to all the defendants except the sergeant-at-arms. They, being members of the house, were held to be protected from prosecution for their action. But, as to Thompson, the judgment was reversed, and the cause remanded for further proceedings. In the supreme court the questions involved received great consideration; and it was held that the subject-matter of the investigation was judicial, and not legislative, and that there -was no power in congress, or in either house, on the allegation that an insolvent debtor of the United States was interested in a private business partnership, to investigate the affairs of that partnership, and, consequently, no authority to compel a witness to testify on the subject.
“The house of representatives,” said the court, “has the sole right to impeach officers of the government, and the senate to try them. Were the question of such impeachment before either body acting in its appropriate sphere on that subject, we see no reason to doubt the right to *253compel "the attendance of witnesses, and their answer to proper questions, in the same manner and by the use of the same means that courts of justice can in like cases. Whether the power of punishment in either house by fine or imprisonment goes beyond this or not, wo are sure that no person can be punished for contumacy as a witness before either house, unless his testimony is required in a matter into which that house has jurisdiction to inquire, and 'ice fed equally sure thal neither of lítese bodies possesses the general power of 'making 'inquiry into the private affairs of the citizen.” And again: “If the investigation which the committee was directed to make was judicial in its character, and could only Iks properly and successfully made by a court of justice, and if it related to a matter wherein relief or redress could ho had only by a judicial proceeding, we do not, after what has been said, doom it necessary to discuss the proposition that the power attempted to be exercised was one confided by the constitution to the judicial, and not to the legislative, department of the' government. We think it equally dear that, the power asserted, is judicial, and not legislative.” And again: “The resolution adopted as a sequence of the preamble contains no hint of any intention of final action by congress on the subject. In all the argument on the case no suggestion has been made of what the house of representatives or the congress could have done in the way of remedying the wrong, or securing the creditors of Jay Cooke & Co., or even the United States. Was it to he simply a fruitless investigation into the personal affairs of individuals? . If so, the house of representatives had no power or authority in the matter more than any other equal number of gentlemen, interested for the government of their cowntry. By fruitless, wo mean that it could result in no valid legislation on the subject to which the inquiry referred.”
When the case wont back to the supreme court of the District of Columbia, and was tried, the plaintiff recovered a verdict for $60,000 against the sergeant-at-arms. A now trial having been granted for excessive damages, the plaintiff recovered on the second trial a verdict for $37,-500. This amount was subsequently reduced to §20,000, which was paid by order of congress, with interest and costs of suit. 23 St. at Large, 467: IMacArthur & Mackey, 416, 432.
This ease will stand for all time as a bulwark against the invasion of the right of the citizen to prelection in his private affairs against the unlimited scrutiny of investigation by a congressional committee. The courts are open to the United Stales as they are to the private citizen, and both can there secure, by regular proceedings, ample protection of all rights and interests which arc entitled to protection under a government of a written constitution and laws.
The act of congress not only authorizes a searching investigation into the methods, affairs, and business of the Central Pacific Railroad Company, but it makes it the duty of the railway commission to inquire into, ascertain, and report whether any of the directors, officers, or employes of that company have been, or are now, directly or indirectly, interested, and to wliat extent, in any railroad, steam-ship, telegraph, express, mining, construction, or other business company or corporation, and with which any *254agreements, undertakings, or leases have been made or entered into. There are over 100 officers, principal and minor, of the Central Pacific Railroad Company, and nearly 5,000 employes. It is not unreasonable to suppose that a large portion of these have some interest, as stockholders or otherwise, in some other company or corporation with which the railway company may have an agreement of some kind, arid it would be difficult to state the extent to which the explorations of the commission into the private affairs of these persons may not go if the mandate of the act could be fully carried out. But in accordance with the principles declared in the case of Kilbourn v. Thompson, and the equally important doctrines announced in Boyd v. U. S., the commission is limited in its inquiries as to the interest of these directors, officers, and employes in any other business, company, or corporation to such matters as these persons may choose to disclose. They cannot be compelled to open their books, and expose such other business to the inspection and examination of the commission. They Avere not prohibited from engaging in any other lawful business because of their interest in and connection with the Central Pacific Railroad Company, and that other business might as well be the construction and management of other railroads as the planting of vines, or the raising of fruit, in Avhich some of those directors and officers ancl employes have been in fact engaged. And they are entitled to the same protection and exemption from inquisitorial investigation into such business as ariy other citizens engaged in like business.
With reference to the vouchers respecting which the principal interrogatories are propounded, and to which we are asked to compel answers from the witness, it is conceded by the commission on this motion that the moneys covered by them were not charged against the United States in ascertaining the net earnings of the company. If such were the case, it is difficult to see what interest the United States can have in the disposition of those moneys. Be that as it may, the federal courts cannot, upon that concession, aid the commission in ascertaining Iioav the moneys Avere expended. Those courts cannot become the instruments of the commission in furthering its investigation. Their power, its nature and extént, is defined by the constitution. The government established by that instrument is one of delegated powers, supreme in its prescribed sphere, but without authority beyond it. No department of it can exercise any powers not specifically enumerated or necessarily implied in those enumerated. Such is the teaching of all of our great jurists, and the tenth amendment declares that “the poAvers not delegated to the United States by the constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.” Any legislation of congress beyond the limits of the powers delegated is an invasion of the rights reserved to the states or to the people, and is necessarily void. The first section of the third article of the constitution declares that “the judicial power of the United States shall be vested in one supreme court, and such inferior courts as congress may, from time to time, ordain and establish.” The second section of the same article declares that “the ju*255dicial power shall extend to all cases, in law and equity, arising under this constitution, the laws of the United States, and treaties made, or which shall be made, under their authority; to all cases affecting ambassadors, other public ministers, and consuls; to all cases of admiralty and maritime jurisdiction; to controversies to which the United States shall be a party; to controversies between two or more states; between a state and citizens of another state; between citizens of different states; between citizens of the same state claiming lands under grants of different states; and between a state, or the citizens thereof, and foreign states, citizens, or subjects.”
This section was modified by the eleventh amendment, declaring that “the judicial power shall not he construed to extend to any suit, in law or equity, commenced or prosecuted against one of the United States by citizens of another state, or by citizens or subjects of any foreign state.” As thus modified, the section states all the cases and controversies in which the judicial power of the United States can be exercised, except those arising on a petition for a writ of habeas corpus, which is regarded as a suit for one’s personal freedom.1 The judicial power of the United States is therefore vested in the courts, and can only be exercised by them in the cases and controversies enumerated, and in petitions for units of habeas corpus. In no other proceedings can that power be invoked, and it is not competent for congress to require its exorcise in any other way. Any act providing for such exercise would be a direct invasion of the rights reserved to the states or to the people; and it would be the duty of the court to declare it null and void. Story says, in his Commentaries on the Constitution, that “the functions of the judges of the courts of the United States arc strictly and exclusively judicial. They cannot, therefore, be called upon to advise the president in any executive measures, or to give extrajudicial interpretations of law, or to act as commissioners in cases of pensions or other like proceedings.” Section 1777.
The judicial article of the constitution mentions cases and controversies. The term “controversies,” if distinguishable at all from “cases,” is so in that it is less comprehensive that the latter, and includes only suits of a civil nature. Chisholm v. Georgia, 2 Dall. 431, 432; 1 Tuck. Bl. Comm. App. 420, 421. By cases and controversies are intended the claims of litigants brought before the courts for determination by sucli regular proceedings as are established bylaw or custom for the protection or enforcement of rights, or the prevention, redress, or punishment of wrongs. Whenever the claim of a party under the constitution, laws, or treaties of the United States takes such a form that the judicial power is capable of acting upon it, then it has become a case. The term implies the existence of present or possible adverse parties whoso contentions are submitted to the court for adjudication.
*256In Osborn v. U. S., 9 Wheat. 819, the supreme court, speaking by Chief Justice Marshall, after quoting the third article of the constitution declaring the extent of the judicial power of the United States, said:
“This clause enables the judicial department to receive jurisdiction to the full extent of the constitution, laws, and treaties of the United States, when any question respecting them shall assume such a form that the judicial power is capable of acting oil it. That power is capable of acting only when the subject is submitted to it by a party who asserts his rights in the form prescribed by law. It then becomes a case, and the constitution declares that the judicial power shall extend to all cases arising under the constitution, laws, and'treaties of the United States.”
In his Commentaries on the Constitution, Mr. Justice Story says:
“It is clear that the judicial department is authorized to exercise jurisdiction to the full extent of the constitution, laws, and treaties of the United States, whenever any question respecting them shall assume such a form that the judicial power is capable of acting upon it. When it has assumed such a form, it then becomes a case; and then, and not till then, the judicial power attaches to it. A case, then, in the sense of this clause of the constitution, arises when some subject touching the constitution, laws, or treaties of the United States is submitted to the courts by a party who asserts his rights in the form prescribed by law.”
And Mr. Justice Story refers in a note to the speech of Marshall on the case of Robbins, in the house of representatives, before he became chief justice, which contains a clear statement of the conditions upon which the judicial power of the United States can be exercised. His language was:
“By extending the judicial power to all cases in law and equity, the constitution has never been understood to confer on that department any political power whatever. To come within this description, a question must assume a legal form for forensic litigation and judicial decision. There must be parties to come into court, who can be reached by its process, and bound by its power; whose rights admit of ultimate decision by a tribunal to which they are bound to submit.”
The proceedings to obtain testimony upon letters rogatory to be used in the courts of foreign countries is not, as suggested by counsel, an exception to this doctrine. There are certain powers inherent in all courts. The power to preserve order in their proceedings, and to punish for contempt of their authority, are instances of this kind. And by jurists and text writers the power of the courts of record of one country, as a matter of comity, to furnish assistance, so far as is consistent with their own jurisdiction, to the courts of another country, by taking the testimony of witnesses to be used in the foreign country, or by ordering it to be taken before a magistrate or commissioner, has also been classed among their inherent powers. “For by the law of nations,” says Greenleaf, “courts of justieq of different countries are bound mutually to aid and assist each other, for the furtherance of justice; and hence, when the testimony of a foreign witness is necessary, the court before which the action is pending may send to the court within whose jurisdiction the witness resides a writ, either jjatent or close, usually termed a letter roga-tory, or a commission sub mutux mcissitudinis obtentuac in juris subsidium, *257from those words contained in it. By this instrument the court abroad is informed of the pendency of the cause, and the names of the foreign witnesses, and is requested to cause their depositions to be taken in due course of law, for the furtherance of justice, 'with an offer on the part of the iriba/iial making the request to do the like for the other in a similar case.” Treatise on Evidence, vol. 1, § 320. The comity in behalf of which this power is exercised cannot, of course, be invoked by any mere investigating commission. And it wouid seem that, by act of congress, the power of the federal courts in this respect has been restricted to oases in which a foreign government is a party or has an interest. Rev. St. § 4071.1
The act of congress creating the railway commission in terms provides, as already stated, that it may invoke the aid of any circuit or district court to require the attendance of witnesses) and the production of books, papers, and documents relating to the subject of inquiry; and empowers the court, in case of contumacy or refusal of persons to obey subpoenas to them, to issue orders requiring them to appear before the commissioners, or either of them, and produce the books and papers ordered, and give evidence touching the matters in question, and to punish disobedience to its orders; and does not appear to leave any discretion in the matter with the court. It would seem as though congress intended that the court should make the orders sought upon the mere request of the commissioners, without regard to the nature of the inquiry. It is difficult to believe that it could have intended that the court should thus bo the mere executor of the commissioners’ will. And yet, if the commissioners are not bound, as they have asserted, by any rules of evidence in their investigations, and may receive hearsay, ex parte statements, and information of every character that may be brought to their attention, and the court is to aid them in this manner of investigation, there can be no room for the exercise of judgment as to the propriety of the questions asked, and the court is left merely to direct that the pleasure of the commissioners in the line of their inquiries be carried out. But if *258it was expected that the court, when its aid is invoked, should examine the subject of the inquiries to see their character, so as to be able to determine the propriety and pertinency of the questions, and the propriety and necessity of producing the books, papers, and documents asked for before the commission, then it would be called upon to exercise advisory functions in an administrative or political proceeding, or to exercise judicial power. If the former, they cannot be invested in the court; if the latter, the power can only be exercised in the cases or controversies enumerated in the constitution, or in cases of habeas corpus.
The provision of the act authorizing the courts to aid in the investigation in the manner indicated must therefore be adjudged void'. The federal courts, under the constitution, cannot be made the aids to any investigation by a commission or a committee into the affairs of any one. If rights are to be protected or wrongs redressed by any investigation, it must be conducted by regular proceedings in the courts of justice in cases authorized by the constitution.
The inability of the courts of the United States to exercise power in any other than regular judicial proceedings was decided in Hayburn’s Case as early as 1792. 2 Dall. 409. In March of that year, congress passed an act providing that invalid officers, soldiers, and seamen of the Revolution should be entitled to certain pensions proportionate to the extent of their disability, and devolved upon the circuit court of the United States of the district, where the invalids resided, the duty of examining the proofs presented of the nature and extent of the disability, and of determining what amount of their monthly pay would be equivalent to the disability ascertained, and to certify the same to the secretary of war, who was to place the names of the applicants returned on the pension list of the United States in conformity thereto, unless where he had cause to suspect imposition or mistake, in which case he was authorized to withhold the name of the applicant from the list, and report the same to congress at its next session. 1 St. at Large, 244, §§ 2, 4. Every circuit judge, except one who did not have the question before him, was of opinion that the law was unconstitutional and void. From a statement of Mr. Justice Curtis, in a note appended to the report of the case, it would seem that the judges were of opinion that the power devolved upon them by the act was not judicial in the sense of the constitution, and, if judicial, that their decisions could not be subject to the revision of the secretary of war, or of the congress of the United States. Plainly, the power exercised by them in determining the extent to which the invalids were entitled to the pensions provided upon the proof produced was in its nature judicial, for it required examination of evidence and judgment thereon; but it was not judicial in the sense of the constitution, under which judicial power can be exercised only in the cases enumerated in that instrument. The judges forwarded their conclusions to President Washington, and the act was subsequently repealed.
A suit being afterwards brought against one Yale Todd to recover back the amount of a pension paid to him, the question of the validity of the act came before the supreme court, and judgment was rendered in favor *259of the United States for the money. This case will be found stated at length by Chief Justice Tanky in a note to the report of U. S. v. Ferreira, 13 How. 52. “This decision,” said that great chief justice, “has ever since been regarded as constitutional law, and followed by every department of the government; by the legislative and executive branches, as well as the judiciary.” Gordon v. U. S., 117 U. S. 697, 703.
The conclusion we have thus reached disposes of the petition of the railway commissioners, and renders it unnecessary to consider whether the interrogatories propounded were proper in themselves, or were sufficiently met by the answers given by Mr. Stanford, or whether any of them were open to objection for the assumptions they made, or the imputations they implied. It is enough that the federal courts cannot be made the instruments to aid the commissioners in their investigations. It also renders it unnecessary to make any comment upon the extraordinary position taken by them according to the statement of the respondent, to which we have referred, that they did not regard themselves bound in their examination by the ordinary rules of evidence, hut would receive hearsay and ex parte statements, surmises, and information of every character that might be called to their attention. It cannot be that the courts of the United States can bo used in furtherance of investigations in -which all rules of evidence may be thus disregarded.
The motion of the district attorney for a peremptory order upon the witness to answer the interrogatories as set forth in the petition of the railway commission is therefore denied, and the order to show cause is discharged.
Note by the Court. Nor is there anything- in the jurisdiction exercised by the LTniicd States courts over proceedings of grand juries, or in aid of their deliberations, or in aid of proceedings to perpetuate testimony, which militates against the viewtaken in the opinion. The judicial power of the courts of the United States extending to the ease's and controversies enumerated in the constitution, their jurisdiction necessarily covers all proceedings taken from the formal commencement of such oases and controversies to the execution of the judgments rendered therein. A certain class of offenders can only he prosecuted in the'federal courts through the indictment or presentment of a grand jury. Article 5 of Amendments. Over, therefore, the proceedings of such bodies those courts can exercise jurisdiction, and in aid of their deliberations can issue proems, and compel the attendance of witnesses, and require them to answer any proper questions propounded to them, and in ease of refusal may punish them as for a contempt.
Proceedings to perpetuate testimony, where litigation is expected or apprehended, are wit bin the ordinary jurisdiction of courts of equity, and come under the designation of cases in equity" in the constitution. The nature and requisites of a hill tiled for that purpose are fully described in Story, Eq. Pl. c. 7. It must state the subject in relation to which the plaintiff desires to preserve testimony, in what way he is interested in that subject, the names of the contemplated or apprehended litigants who are named as defendants, and the interests they have in the subject, or claim to have; and a subpoena must ho issued tliereon and served as in other cases in equity.