William O. Douglas

“ For we conclude that the injunction issued by the District Court was 'necessary in aid of its jurisdiction' and thus permitted under the exceptions specifically allowed by Congress.
The state court injunction restrains conduct which the District Court was asked to enjoin in the § 10 (l) proceeding brought in the District Court by the Board's Regional Director against the union. In order to make the § 10 (l) power effective the Board must have authority to take all steps necessary to preserve its case. ”

“ The Regional Director, acting on behalf of the General Counsel, issued an unfair labor practice complaint against the union on that limited basis. On the same day, he petitioned the Federal District Court for an injunction restraining such conduct of the union, pending final adjudication by the Board, as required by § 10 (l) of the Act. ”

“ I. The District Court had jurisdiction of the subject matter, because this is a 'civil action or proceeding' arising under an Act of Congress 'regulating commerce.' 28 U.S.C. § 1337, 28 U.S.C.A. § 1337. The National Labor Relations Act is a law 'regulating commerce' (National Labor Relations Board v. Jones & Laughlin Steel Corp., 301 U.S. 1, 57 S.Ct. 615, 81 L.Ed. 893) ”