dissenting.
The Court correctly recognizes (1) that it is violative of employees’ rights guaranteed by § 7, and an unfair labor practice by an employer under § 8 (a) and by a labor union under § 8 (b), of the National Labor Relations Act, for an employer and a labor union to enter into a contract providing either for the recognition by the employer of the union as the representative of its employees or that its employees must become and remain members of the union, unless the union, at that time, represented a majority of the employees in the unit, (2) that “The maintaining of such an agreement in force is a continuing violation of the Act,” and (3) that the bargaining contract involved in this case not only recognized the union as the exclusive bargaining representative of the employees, but also required the employees to become and remain members of the union, although the union did not then represent a majority of the employees in the unit.*
Despite the foregoing, the Court holds, I think, with deference, quite inconsistently and erroneously, that § 10 (b) of the Act barred the issuance of a complaint, *434upon an employee’s charge filed with and served by the Board 10 months after the making of the contract, based not upon the making of the contract, but alleging that, within and throughout the period of six months preceding the filing and service of the charge, the employer and the union required the employees to become and remain members of the union, and, once in each of those six months, caused certain sums to be deducted from the employees’ wages and paid over to the union, all without the authorization of the employees.
The Court, noting the employer-union contention that the contract was “tainted” only by its “unlawful execution,” and that “since a complaint based upon that unfair labor practice [would be] barred” by § 10 (b), that event could not be utilized “to infuse with illegality the otherwise legal union security clause or its enforcement,” adopts that argument as presenting the “correct view.” (Emphasis added.)
Surely the fact that a prosecution for the making of a “tainted” contract is barred by limitations does not “infuse” the “tainted” contract with legality. Moreover, I respectfully submit that the complaint here was not based upon the “tainted” contract, and that its unlawful execution was not utilized “to infuse [the always illegal contract] with illegality.” Rather, the complaint here was based upon and limited to independent acts of the employer and the union, committed within six months preceding the filing and service of the charge, that deprived the employees of rights guaranteed to them by § 7, resulting in unfair labor practices under § 8; and the fact that prosecution for the illegal execution of the “tainted” contract is time-barred, as an independent wrong, may not be utilized “to infuse with” legality the illegal “union security clause or its enforcement.”
It is important carefully to note what it is that § 10 (b) bars. It says, in relevant part, that “no complaint shall *435issue based upon any unfair labor practice occurring more than six months prior to the filing of the charge . . . .” (Emphasis added.) The bar is, then, against the issuance of a “complaint” that is “based upon” acts “occurring more” than six months prior to the filing of the charge. In the plainest possible sense, then, it does not bar the issuance of a complaint based upon acts occurring within six months of the filing of the charge. The complaint that was issued here was based upon acts occurring within six months of the filing of the charge. And the Board rested its decision solely on those acts.
But the Court holds that, although § 10 (b) is only a statute of limitations, evidence of the illegality of the contract is inadmissible, in the circumstances of this case, because it would serve “to cloak with illegality that which was otherwise lawful,” and would permit a time-barred event “to be so used [as to revive] a legally defunct unfair labor practice.” This conclusion gives hip rather than heed to the conceded rule that “the maintaining of such an agreement in force is a continuing violation of the Act,” for it makes incompetent all relevant evidence that may be adduced to prove the “continuing violation.” Moreover, such a rule is contrary to the decisions of this Court and to every decision of the Courts of Appeals upon the point to which our attention has been directed.
In Federal Trade Comm’n v. Cement Institute, 333 U. S. 683, this Court held it to be:
“well within the established judicial rule of evidence that testimony of prior or subsequent transactions, which for some reason are barred from forming the basis for a suit, may nevertheless be introduced if it tends reasonably to show the purpose and character of the particular transactions under scrutiny. Standard Oil Co. v. United States, 221 U. S. 1, 46-47; United States v. Reading Co., 253 U. S. 26, 43-44.” 333 U. S., at 705.
*436To the same effect, but directly dealing with unfair labor practices, are Paramount Cap Mfg. Co. v. Labor Board, 260 F. 2d 109, 112-113 (C. A. 8th Cir.); Labor Board v. Gaynor News Co., 197 F. 2d 719, 722 (C. A. 2d Cir.), aff’d sub nom., Radio Officers v. Labor Board, 347 U. S. 17; Katz v. Labor Board, 196 F. 2d 411, 415 (C. A. 9th Cir.); Labor Board v. General Shoe Corp., 192 F. 2d 504, 507 (C. A. 6th Cir.); Labor Board v. Clausen, 188 F. 2d 439, 443 (C. A. 3d Cir.); Superior Engraving Co. v. Labor Board, 183 F. 2d 783, 791 (C. A. 7th Cir.).
In the Katz case, almost identical with this one on the point in issue, the Court specifically rejected the contention that, inasmuch as more than six months had expired from the date of the execution of the tainted contract, the complaint, based upon acts occurring within six months of the charge, was barred by § 10 (b), saying:
“While . . . the mere execution of the agreement on December 17, 1948, constituted an unfair labor practice, there is no doubt but that the continuous enforcement of the agreement thereafter within the six months period prior to the filing of the charge, was an unfair labor practice, and with respect to this continued and continuous enforcement of the illegal union shop agreement, the prosecution of the proceeding was not barred by limitations.” 196 F. 2d, at 415.
In the Gaynor case, the Court, after pointing out that although the tainted contract had been executed more than six months prior to the filing of the charge, and its execution was therefore barred as an independent subject of punishment by § 10 (b), observed that enforcement of the contract was “a continuing offense,” and held that the complaint, based only on acts occurring within six months *437of the filing of the charge, was lawfully issued and “in all respects valid." 197 F. 2d, at 722.
Although still recognizing that enforcement of a tainted labor contract “is a continuing violation” of the law, the Court further says that this is true “solely by reason of circumstances existing only at the date of execution”; and it therefore concludes that evidence of the taint is inadmissible in a proceeding to punish unlawful conduct occurring from enforcement of the contract within six months of the filing of a charge. I respectfully submit it is plain that this reasoning negates the conceded rule that enforcement of a tainted contract is “a continuing offense.” The Court’s reasoning, inconsistently, would at once both recognize, and deny any means of proving, the “continuing offense.”
Analytical curiosity provokes the query whether such an illegal contract, openly posted in the plant but not made effective in practice until the first day of the seventh month, would then become so “infused” with legality as to be unassailable by the employees — not because its enforcement is not “a continuing offense,” but, rather, because, under the Court’s rule, there can be no competent evidence of its illegality. If so, the rule of “continuing offense” is utterly destroyed. If not, the Court’s rule that there can be no competent evidence of the continuing violation must give way. The two theories are diametrically opposed and self-destructive. Section 10 (b) does not at all deal with the competency or admissibility of evidence. Surely, as the cited cases hold, any evidence which shows that continuing enforcement of the contract is or is not an offense under the Act is competent under the law.
But there is even a more fundamental consideration which, for me, settles this issue beyond all controversy. While it is the burden of the General Counsel of the Board *438to prove his case, all he need do, initially at least, is to make a prima facie case. He may do this, in a case like the present, simply by putting on evidence showing that the employer and the union, within six months preceding the filing of the charge, required the employees to become and remain members of the union and to submit to deduction of dues from their wages without asking them for authorization and without any election, or Board certification of the union. That evidence alone would raise prima facie the issue: By what right was this done? That issue would call for a defense, and the burden of producing the defense would necessarily fall upon the employer and the union. Surely it will not be said that anything in § 10 (b), or elsewhere in the law, makes incompetent all evidence that might be adduced by the employer and the union to meet their burden and justify their action. If, as I submit cannot be denied, such evidence is competent when offered by the employer and the union, it must likewise be competent when, if he so elects, it is offered by the General Counsel of the Board. Here, at the very least, the General Counsel made a prima facie case of continuing violations of the law within the six months preceding the filing of the charge, the employer and the union made no effort to show the legality of their conduct in the period complained of.
The Court attributes to its rule the virtues of quieting “stale claims” and of “stabiliz[ing] existing bargaining relationships.” I cannot agree that it would do either, for employee rights, occurring within six months of the filing of the charge, are not “stale claims,” and deprivation of those rights which, as the Court of Appeals said, “rankles at least once a month in the mind of [the employees] offended,” is not conducive to industrial peace and would not — certainly not legally — “stabilize existing bargaining relationships.” At all events, and however this may be, these matters were for Congress; and the cardinal pur*439poses of the National Labor Relations Act, contained in § 7, were to guarantee to employees the right to join or assist labor organizations “of their own choosing” or to refrain from such activities. Surely, the continuing offense of enforcing a contract, made by an employer with a union which was not of the employees’ “own choosing,” was not intended by Congress to be left without a remedy. Congress did not intend to create and “to hold' out to [employees] an illusory right for which it was denying them a remedy.” Graham v. Brotherhood of Firemen, 338 U. S. 232, 240. Certainly, “any limitation on the employees’ right[s] [under] §§ 7 and 8 . . . must be more explicit and clear than it is here in order to restrict them at the very time they may be most needed.” Mastro Plastics Corp. v. Labor Board, 350 U. S. 270, 287. See also Labor Board v. Lion Oil Co., 352 U. S. 282, 289.
Believing that the Board and the Court of Appeals correctly decided this case, I would affirm the judgment.
In fact, the undisputed testimony was that the union did not then represent a single one of the employees, and that the employer acceded to the union’s demand for recognition and entered into the contract simply because the union had it “over a barrel.”