Majority — Vinson C.J.
delivered the opinion of the Court.
The constitutionality of the strike vote provision of the Michigan labor mediation law[1] is before us in this case. Appellants struck against Chrysler Corporation in May, 1948, without conforming to the prescribed state procedure. The strike was called to enforce demands for
1 Mich. Stat. Ann. (Cum. Supp. 1949) §§ 17.454 (1) et seq.; Mich. Comp. Laws, 1948, §§ 423.1 et seq. At the time of appellants’ strike, the pertinent provisions of the law read as follows: "Sec. 9. No strike or lockout shall take place or be put into effect until and unless each of the steps have been taken and the requirements complied with as provided in this act. “1. In the event the parties thereto are unable to settle any dispute, the employees or their representative, in the case of impending strike, or the employer or his agent, in the case of an impending lockout, shall serve notice upon the board of such dispute together with a statement of the issues involved. . . . not less than 10 days before the strike or lockout is to become effective, or in ease of an industry affected with a public interest or a public utility or hospital, said notice shall be so served not less than 30 days before the strike or lockout is to become effective. “2. Upon receipt of such notice it shall be the duty of the board to exercise the powers herein granted to effect a settlement of such dispute by mediation between the parties. Prior to the calling of an election as provided hereinafter, it shall be the duty of each of the *456 parties to such dispute to actively and in good faith participate in the mediation thereof. . . . “Sec. 9a. In the event that it becomes apparent to the board that there is no reasonable probability of settlement of such dispute by mediation and that further efforts to that end would be without avail, there shall be held in the case of any impending strike, an election upon such issue which election shall be conducted and supervised by the board. In the event either party to said dispute notifies the board in writing . . . that in the opinion of such party, further efforts to settle such dispute by mediation would be without avail, it shall be the duty of the board to cause an election to be held within 10 days of the receipt of such notice unless it is not practical to hold such election within said period, in which event said election shall be held within 20 days of receipt of such notice .... Every employee in the bargaining unit shall be entitled to vote in such election and in order to authorize a strike under the provisions of this act, a majority of all employees in such bargaining unit must vote in favor of such action.” In 1949, the last requirement was amended to read, “a majority of all employees casting valid ballots must vote in favor of such action.” This change is not material to our decision.
Congress has not been silent on the subject of strikes in interstate commerce. In the National Labor Relations Act of 1935, 49 Stat. 449 , 29 U. S. C. § 151 , as amended by the Labor Management Relations Act, 1947, 61 Stat.
2 The court below held that appellants’ acts “rendered [them] subject to threatened criminal prosecution . . . .” 325 Mich, at 254 , 38 N. W. 2d at 422 . See § 22. We are of course bound by this interpretation of the state law.
3 See §§ 7, 2 (3), 13 of both Acts; H. R. Rep. No. 510, 80th Cong., 1st Sess. 59 (1947); S. Rep. No. 105, 80th Cong., 1st Sess. 28 (1947); statement of Senator Taft, 93 Cong. Rec. 3835 (1947), which includes the following: “That means that we recognize freedom to strike when the question involved is the improvement of wages, hours, and working conditions, when a contract has expired and neither side is bound by a contract. . . . We have considered the question whether the right to strike can be modified. I think it can be modified in cases which do not involve the basic question of wages, prices, and working conditions. ... So far as the bill is concerned, we have proceeded on the theory that there is a right to strike and that labor peace must be based on free collective bargaining. We have done nothing to outlaw strikes for basic wages, hours, and working conditions after proper opportunity for mediation.”
4 Congress created a new federal agency, the Federal Mediation and Conciliation Service, to assist in the peaceful settlement of disputes. §§ 202-204.
Finally, the bargaining unit established in accordance with federal law may be inconsistent with that required by state regulation. Though the unit for the Michigan strike vote cannot extend beyond the State’s borders, the unit for which appellant union is the federally certified bargaining representative includes Chrysler plants in California and Indiana as well as Michigan. Chrysler Corp., 42 N. L. R.
5 H. R. 3020, 80th Cong., 1st Sess. §2 (11) (B) (vi) (h) (1947). The legislative history demonstrates that this proposal was rejected on the merits, and not because of any desire to leave the states free to adopt it. See, e. g., H. R. Rep. No. 510, 80th Cong., 1st Sess. 34r-35 (1947); testimony of Governor Stassen, Hearings before Senate Committee on Labor and Public Welfare on S. 55 and S. J. Res. 22, 80th Cong., 1st Sess. 562-65, 572-78, 586-89 (1947).
Auto. Workersv. Wisconsin Board, 336 U.S. 245 (1949), upon which Michigan principally relies, was not concerned with a traditional, peaceful strike for higher wages. The employees’ conduct there was “a new technique for bringing pressure upon the employer,” a “recurrent or intermittent unannounced stoppage of work to win unstated ends.” Id. at 249, 264 . That activity we regarded as “coercive,” similar to the sit-down strike held to fall outside the protection of the federal Act in Labor Board v. Fansteel Metallurgical Corp., 306 U. S. 240 (1939), and to the labor violence held to be subject to state police control in Allen-Bradley Local v. Wisconsin Board, 315 U. S. 740 (1942). In the Wisconsin Auto. Workers case, we concluded that the union tactic was “neither forbidden by federal statute nor was it legalized and approved thereby.” 336 U. S. at 265. “There is no existing or possible conflict or overlapping between the authority of the Federal and State Boards, because the Federal Board has no authority either to investigate, approve or forbid the union conduct in question. This conduct is governable by the State or it is entirely ungoverned.” Id. at 254. Clearly, we reaffirmed the principle that if “Congress has protected the union conduct which the State has forbidden . . . the state legislation must yield.” Id. at 252. That principle is controlling ^ere‘
Reversed.
Mr. Justice Douglas concurs in the result.
Cases cited
- 338 U. S. 953 338 U. S. 953 p. 457, p. 459
- La Crosse Telephone Corp. v. Wisconsin Employment Relations Board 336 U. S. 18 p. 457, p. 459
- Bethlehem Steel Co. v. New York State Labor Relations Board 330 U. S. 767 p. 457, p. 459
- Hill v. Florida ex rel. Watson 325 U. S. 538 p. 457, p. 459
- International Union, U. A. W. A., A. F. of L., Local 232 v. Wisconsin Employment Relations Board 336 U.S. 245 at 265 p. 459
- National Labor Relations Board v. Fansteel Metallurgical Corp. 306 U. S. 240 p. 459
- Allen-Bradley Local No. 1111 v. Wisconsin Employment Relations Board 315 U. S. 740 p. 459