Generally speaking, Congress may of course provide the rules of evidence to be adopted by the federal courts, and itself establish, or empower the courts themselves to establish, the rules governing their procedure in the trial of cases, the preparing and printing of records, the perfecting of appeals, etc. "With reference to the federal legislative authority over the rules of evidence to be followed in the federal courts, it is declared in Potter v. National Bank:20 "It is quite true that the 34th section of the Judiciary Act of 1789 - preserved totidem verbis, in section 721 of the present revision of the statutes - has been construed as requiring the federal courts, in all civil cases at common law, not within the exceptions named, to observe, as rules of decision, the rules of evidence prescribed by the laws of the States in which such courts respectively sit. But that section of the Act of 1789, as does section 721 of the Revised Statutes, expressly excepts from its operations cases 'Where the Constitution, treaties or statutes of the United States otherwise provide.' We have seen that the existing statutes of the United States do 'otherwise provide,' in that they forbid the exclusion of a witness upon the ground that he is a party to or interested in the issue, in any civil action whatever pending in a federal court, except in a certain class of actions, which do not embrace the one now before us. 'In all other respects,' that is, in all cases not provided for by the Statutes of the United States, the laws of the State, in which the federal court sits, constitute rules of decision as to the competency of witnesses in all actions at common law, in equity or in admiralty. It is clear, therefore, that the law of Illinois can have no bearing upon a case which, as here, is embraced or has been provided for by the federal statute." 21

In Bein v. Heath (12 How. 168; 13 L. ed. 939) a ease arising in Louisiana, in which State there was no equity as distinguished from common-law jurisdiction, the court say: "When an injunction is applied for in the circuit court of the United States sitting in Louisiana, the court grants it or not, according to the established principles of equity, and not according to the laws and practice of the State ... in which there is no court of chancery, as distinguished from a court of common law,"

In Sheffield Furnace Co. v. Witherow (149 U. S. 574; 13 Sup. Ct. Rep. 936; 37 L. ed. 853) the court deny that a State by prescribing by statute an action at law can oust a federal court, sitting in equity, of its jurisdiction as such. Quoting Robinson v. Campbell (3 Wh. 212: 4 L. ed. 372) the opinion declares: "A construction that would adopt the state practice in all its extent would at once extinguish, in such States, the exercise of equitable jurisdiction. The acts of Congress have distinguished between remedies at common law and in equity, yet this construction would confound them. The court, therefore, thinks that to effectuate the purposes of the legislature the remedies in the courts of the United States are to be at common law and equity, as distinguished and defined in that country from which we derive our knowledge of those principles."

19 Cf. Columbian Law Rev. IV (1904), p. 589.

Section 914 of the Revised Statutes provides that in the federal courts in civil causes other than equity and admiralty, "the practice, pleadings and forms and modes of proceeding" shall conform - "as near as may be" to the existing practice in the States in which they sit. There is thus left, even as to these causes, opportunity for variance of practice whether because of constitutional necessity, as for example with reference to jury trial, or because of statutory direction. Thus the rules with reference to the compulsory production of documentary evidence, the amendment of pleadings, etc., are fixed by federal statute. So also, it is held that federal judges are not bound by state rules with reference to instructing the jury, the granting of new trials, the submission of special issues to the jury, the preparation of a case for appeal, etc.22

20 102 U. S. l63: 26 L. ed. III.

21 There would seem to be a corresponding inability upon the part of Con-press to fix the rules of evidence and procedure of state courts. Thus, for example, while it is competent for Congress to declare that certain unstamped documents shall not be received as evidence in the federal courts, they might still be so received in the state courts. Latham v. Smith, 45 III. 293; Bowlin v. Commonwealth, 2 Bush, 5.