22 22 Opinion of the Court. Mr. Roy B. Thomson, with whom Mr. O. H. Dean, Mr. Albert E. Stoll, Mr. H. M. Langworthy and Mr. M. W. Borders were on the briefs, for petitioner. Mr. William S. Hogsett, with whom Mr. Murat Boyle and Mr. Mont T. Prewitt were on the briefs, for respondent. MR. JUSTICE HOLMES delivered the opinion of the Court. This is a suit for personal injuries suffered by the plaintiff (the respondent here) upon the Chicago Great Western Railroad on January 3, 1920, while that road was under federal control. The suit was brought against Walker D. Hines, the Director General, on January 29, 1920, in the Circuit Court of Jackson County, Missouri. The cause of action arose in another county and the plaintiff then and when the suit was brought resided in Illinois. By General Order 18-A it was ordered that "all suits against carriers while under federal control must be brought in the county or district where the plaintiff resided at the time of the accrual of the cause of action or in the county or district where the cause of action arose." The defendant pleaded a general denial and also that the Court was without jurisdiction because of the foregoing facts. The plaintiff by replication relied upon the invalidity of the order, a point now decided against him. Alabama & Vicksburg Ry. Co. v. Journey, 257 U. S. 111. On February 25, 1921, the plaintiff amended and John Barton Payne, Director General of Railroads and agent designated by the President under Transportation Act, 1920, was substituted by agreement as successor of Hines and according to the record the "substituted defendant entered his appearance in said cause and adopted the answer theretofore filed by said Walker D. Hines, defendant." It was not disputed and was stated Opinion of the Court. 263 U.S. by the Court below that by Missouri practice the defendant had a right to unite a plea to the jurisdiction and a defence on the merits, but it was held by the Court of Appeals, affirming a judgment for the plaintiff, that the provision in General Order 18-A went only to the venue of the action and was waived by the appearance of Payne. A similar effect was attributed to the appearance of the present petitioner Davis in the place of Payne. A writ of certiorari was denied by the Supreme Court of the State. We are of opinion that the judgment must be reversed. Whatever springes the State may set for those who are endeavoring to assert rights that the State confers, the assertion of federal rights, when plainly and reasonably made, is not to be defeated under the name of local practice. Even if the order went only to the venue and not to the jurisdiction of the Court, each Director General in turn plainly indicated that he meant to adopt the position of his predecessor, and to insist that the suit was brought in the wrong county. His lawful insistence cannot be evaded by attempting a distinction between his appearance and his substantially contemporaneous adoption of the plea. Indeed when the law requires him to unite his defence on the merits, which imports an appearance pro hac vice, with his preliminary plea, it is hard to understand how any effect could be attributed to the statement that he appeared. The state courts may deal with that as they think proper in local matters but they cannot treat it as defeating a plain assertion of federal right. The principle is general and necessary. Ward v. Love County, 253 U. S. 17, 22. If the Constitution and laws of the United States are to be enforced, this Court cannot accept as final the decision of the state tribunal as to what are the facts alleged to give rise to the right or to bar the assertion of it even upon local grounds. Creswill v. Grand Lodge Knights of 22 Statement of the Case. Pythias, 225 U. S. 246. This is familiar as to the substantive law and for the same reasons it is necessary to see that local practice shall not be allowed to put unreasonable obstacles in the way. See American Ry. Express Co. v. Levee, decided this day, ante, 19. The Transportation Act, 1920, February 28, 1920, c. 91, § 206, (a) and (d); 41 Stat. 456, 461, 462, in no way invalidates a defence good when it was passed. Judgment reversed. DIRECTOR GENERAL OF RAILROADS v. KASTEN BAUM. CERTIORARI TO THE SUPREME COURT OF THE STATE OF NEW YORK. No. 39. Argued October 3, 4, 1923-Decided November 12, 1923. Under § 10 of the Federal Control Act, an action for false imprisonment may be maintained against the Director General of Railroads by a person, who, at the instigation of railroad detectives, (agents of the Director General,) acting without probable cause, was arrested without warrant for a theft of freight from the railroad while under federal control. P. 27. 198 App. Div. 966; 199 id. 957, affirmed. CERTIORARI to the Supreme Court of New York to review a judgment for damages recovered by the respondent from the petitioner in an action for false imprisonment. The judgment was affirmed by the Appellate Division and leave to appeal to the Court of Appeals was denied. Mr. Thomas R. Wheeler, with whom Mr. Lyman M. Bass was on the brief, for petitioner. Mr. Israel G. Holender for respondent. MR. CHIEF JUSTICE TAFT delivered the opinion of the Court. Opinion of the Court. 263 U.S. Respondent brought an action in the Supreme Court of Erie County, New York, against the Director General of Railroads, seeking damages for false imprisonment and malicious prosecution. The trial court, at the close of the plaintiff's case, dismissed the cause of action for malicious prosecution, but allowed the trial to proceed to verdict and judgment for $500 for false imprisonment. The judgment was affirmed by the Appellate Division of the Supreme Court and a motion for leave to appeal was denied by the Court of Appeals of the State. The brief for petitioner on the merits states the single question to be: Does an action for false arrest lie against the petitioner, an officer of the United States Government, under the provisions of § 10 of the Act of Congress of March 21, 1918, c. 25, 40 Stat. 451, providing for federal control of carriers? Twenty-one tubs of butter were taken from a freight car of the Lehigh Valley Railroad in Buffalo. A trolley car of that city, late at night, collided with a horse and wagon and, in the wreck which followed, the stolen tubs of butter were discovered. Two men who had been driving the wagon escaped. The detective force of the railway company sought to discover the owner of the horse and thought they had traced the ownership to Kastenbaum, who was a huckster. The railroad detective notified the police authorities of the city, who detailed two policemen to accompany him to Kastenbaum's house, where they arrested him without warrant. They took him to a police station and kept him there over night and until he was released the next day on bail. He was brought to a hearing before an examining magistrate on a charge of grand larceny and burglary. After four or five adjournments, at the instance of the prosecution, the magistrate discharged Kastenbaum. His horse proved to be one of another color. Under the charge of the court 25 Opinion of the Court. the jury were permitted to return only compensatory damages. Section 10 of the Federal Control Act provides: "That carriers while under Federal control shall be subject to all laws and liabilities as common carriers, whether arising under State or Federal laws or at common law, except in so far as may be inconsistent with the provisions of this Act or any other act applicable to such Federal control or with any order of the President. Actions at law or suits in equity may be brought by and against such carriers and judgments rendered as now provided by law; and in any action at law or suit in equity against the carrier, no defense shall be made thereto upon the ground that the carrier is an instrumentality or agency of the Federal Government." By General Order No. 50, the Executive so limited suits to be brought against carriers for injuries to person or property under the section as to exclude those for recovery of fines, penalties and forfeitures. As we said in Missouri Pacific R. R. Co. v. Ault, 256 U. S. 554, 563: "The Government undertook as carrier to observe all existing laws; it undertook to compensate any person injured through a departure by its agents or servants from their duty under such law; but it did not undertake to punish itself for any departure by the imposition upon itself of fines and penalties or to permit any other sovereignty to punish it." The action for false imprisonment is in the nature of a trespass for a wrong or illegal act in which the defendant must have personally participated directly or by indirect procurement. The gist of it is an unlawful detention, and that being shown the burden is on the defendant to establish probable cause for the arrest. The want of probable cause, certainly in the absence of proof of guilt or conviction of the plaintiff, is measured by the state of |