delivered the opinion of the Court.
The Michigan State Bar brought this action in January 1959 to enjoin the members of the Brotherhood of Railroad Trainmen1 from engaging in activities undertaken for the stated purpose of assisting their fellow workers, their widows and families, to protect themselves from excessive fees at the hands of incompetent attorneys in suits for damages under the Federal Employers’ Liability Act.2 The complaint charged, as factors relevant to the cause of action, that the Union recommended selected attorneys to its members and their families, that it secured a commitment from those attorneys that the maximum fee charged would not exceed 25% of the recovery, and that it recommended Chicago lawyers to represent Michigan claimants. The State Bar’s complaint appears to be a plea for court protection of un*578limited legal fees. The Union’s answers admitted that it had engaged in the practice of protecting members against large fees and incompetent counsel; that since 1930 it had recommended, with respect to FELA claims, that injured member employees, and their families, consult attorneys designated by the Union as “Legal Counsel”; that prior to March 1959, it had informed the injured members and their families that the legal counsel would not charge in excess of 25% of any recovery; and that Union representatives were reimbursed for transporting injured employees, or their families, to the legal counsel offices.
The only evidence introduced in this case was the testimony of one employee of the Association of American Railroads in 1961 that from 1953 through 1960 a large number of Michigan FELA claimants were represented by the Union’s designated Chicago legal counsel. Based on this evidence and the Union’s admissions set out above, the state trial court in 1962 issued an order enjoining the Union’s activities on the ground that they violated the state statute making it a misdemeanor to “solicit” damage suits against railroads.3 The Union appealed to the Michigan Supreme Court, but before the case was argued on appeal, this Court handed down its decision in Brotherhood of Railroad Trainmen v. Virginia State Bar, 377 U. S. 1 (1964), involving a similar injunction secured by the Virginia State Bar against the Union. We held in that case that the First Amendment guarantees of free speech, petition, and assembly give *579railroad workers the right to cooperate in helping and advising one another in asserting their rights under the FELA. While not deciding every question that possibly could be raised, our opinion left no doubt that workers have a right under the First Amendment to act collectively to secure good, honest lawyers to assert their claims against railroads.
Acknowledging our decision in Trainmen, the Michigan Supreme Court remanded the instant case to the state trial court with permission for amendment of the complaint “to seek, if it be so advised, relief not inconsistent with the Supreme Court’s said opinion.” 374 Mich. 152, 155, 132 N. W. 2d 78, 79. After remand, the State Bar made a motion for further proceedings. That motion was heard on February 5, 1965, at which time the Bar declined to amend its complaint. For reasons not explained in the record, the case lingered in the trial court until May 24, 1968. On that date, after a motion for judgment by the State Bar and arguments on the motion, the trial court adopted verbatim the injunction entered in the Virginia state courts after our remand in Trainmen.
In affirming the trial court decree, the material part of which is set out below,4 the Michigan Supreme Court gave our holding in Trainmen the narrowest possible *580reading,5 focusing only on the specific literal language of the injunctive provisions challenged in that case rather than the broad range of union activities held to be protected by the First Amendment. Similarly, the Michigan court erroneously restricted our holding in United Mine Workers v. Illinois State Bar Assn., 389 U. S. 217 (1967), to “the operative portion” of the Illinois decree prohibiting any financial connection between the attorney and the Union. The Michigan Supreme Court failed to follow our decisions in Trainmen, United Mine Workers, and NAACP v. Button, 371 U. S. 415 (1963), upholding the First Amendment principle that groups can unite to assert their legal rights as effectively and economically as practicable. When applied, as it must be, to the Union’s activities reflected in the record of this case, the First Amendment forbids the restraints imposed by the injunction here under review for the following among other reasons.
First. The decree approved by the Michigan Supreme Court enjoins the Union from “giving or furnishing legal advice to its members or their families.” Given its broadest meaning, this provision would bar the Union’s members, officers, agents, or attorneys from giving any kind of advice or counsel to an injured worker or his family concerning his FELA claim. In Trainmen we upheld the commonsense proposition that such activity is protected by the First Amendment. Moreover, the *581plain meaning of this particular injunctive provision would emphatically deny the right of the Union to employ counsel to represent its members, a right explicitly upheld in United Mine Workers6 and NAACP v. Button.
We cannot accept the restricted interpretation of this provision urged by the State Bar, and accepted by our Brother Harlan, that it only prohibits the Union or its members themselves from “practicing law.” The record is devoid of any evidence or allegation of such conduct on the part of the Union or its members. A decree must relate specifically and exclusively to the pleadings and proof. If not so related, the provision, because of its vagueness, will jeopardize the exercise of protected freedoms. This injunction, like a criminal statute, prohibits conduct under fear of punishment. Therefore, we look at the injunction as we look at a statute, and if upon its face it abridges rights guaranteed by the First Amendment, it should be struck down. Our statement in NAACP v. Button concerning the statute there in question is equally applicable to the injunction now before us: “[W]e cannot assume that, in its subsequent enforcement, ambiguities will be resolved in favor of adequate protection of First Amendment rights.” 371 U. S., at 438.
Second. The decree also enjoins the Union from furnishing to any attorney, the names of injured members or information relating to their injuries. The investigation of accidents by Union staff for purposes of gathering evidence to assist the injured worker or his family in asserting FELA claims was part of the Union practice *582upheld in Trainmen. 377 U. S., at 4 n. 8. It would seem at least a little strange now to hold that the Union cannot communicate that information to the injured member’s attorney.7
Third. A provision of the decree enjoins the members of the Union from.“accepting or receiving compensation of any kind, directly or indirectly, for the solicitation of legal employment for any lawyer, whether by way of salary, commission or otherwise.” The Union conceded that prior to 1959, Union representatives were reimbursed for their actual time spent and out-of-pocket expenses incurred in bringing injured members or their families to the offices of the legal counsel. Since the members of a union have a First Amendment right to help and advise each other in securing effective legal representation, there can be no doubt that transportation of injured members to an attorney’s office is within the scope of that protected activity. To the extent that *583the injunction prohibits this practice, it is invalid under Trainmen, United Mine Workers, and NAACP v. Button.
Fourth. Our Brothers Harlan and White apparently accept the State Bar contention that the provision prohibiting compensation to Union representatives for solicitation refers to compensation paid by the attorney rather than the Union. And so interpreted, it supplements the two provisions which prohibit the Union from sharing in legal fees received by the recommended counsel. There is no basis for this restraint. Such activity is not even suggested in the complaint. There is not a line of evidence concerning such practice in the record in this case. If there is any such suggestion, it is in records in other cases involving other parties in other courts, records upon which we believe our Brother Harlan erroneously seeks to rely. In fact, the explanation for the appearance of the provisions in this decree appears to be the Michigan court’s verbatim adoption of a Virginia injunction issued in a different case on different pleadings relating to different facts. Decrees between litigants should not rest on any such unsupportable basis as this.
Our Brother Harlan appears to concede that the State Bar has neither alleged nor proved that the Union has engaged in the past, is presently engaging, or plans to engage, in the sharing of legal fees. Nonetheless, he suggests that the injunction against such conduct is justified in order to remove any “temptation” for the Union to participate in such activities. We cannot accept this novel concept of equity jurisdiction that would open the courts to claims for injunctions against “temptation,” and would deem potential “temptation” to be a sufficient basis for the issuance of an injunction. Indeed, it would appear that jurisdiction over “temptation” has heretofore been reserved to the churches.
*584An injunction can issue only after the plaintiff has established that the conduct sought to be enjoined is illegal and that the defendant, if not enjoined, will engage in such conduct. In Hitchman Coal & Coke Co. v. Mitchell, 245 U. S. 229, 262 (1917), this Court struck the portions of a decree enjoining a union from picketing and physical violence because there was no evidence that either of these forms of interference was threatened.8 Likewise in the present case, with respect to the prohibition against sharing legal fees, the State Bar simply has made no showing that such conduct was threatened. Indeed, it has made no showing at all. Therefore, that provision of the decree, to use an often quoted slogan, would appear to be not only unjustified, but also '‘arbitrary and capricious.”
Fifth. Finally, the challenged decree bars the Union from controlling, directly or indirectly, the fees charged by any lawyer. The complaint alleged that the Union sought to protect its members from excessive legal fees by securing an agreement from the counsel it recommends that the fee will not exceed 25% of the recovery, and that the percentage will include all expenses incidental to investigation and litigation. The Union in its answer admitted that prior to 1959 it secured such agreements for the protection of its members.
United Mine Workers upheld the right of workers to act collectively to obtain affordable and effective legal representation. One of the abuses sought to be remedied by the Mine Workers’ plan was the situation pursuant to which members “were required to pay forty or fifty per cent of the amounts recovered in damage suits, for attorney fees.” 389 U. S., at 219. The Mine *585Workers dealt with the problem by employing an attorney on a salary basis, thereby providing free legal representation for its members in asserting their claims before the state workmen’s compensation board. The Union in the instant case sought to protect its members against the same abuse by limiting the fee charged by recommended attorneys. It is hard to believe that a court of justice would deny a cooperative union of workers the right to protect its injured members, and their widows and children, from the injustice of excessive fees at the hands of inadequate counsel. Indeed, the Michigan court was foreclosed from so doing by our decision in United Mine Workers.9
In the context of this case we deal with a cooperative union of workers seeking to assist its members in effectively asserting claims under the FELA. But the principle here involved cannot be limited to the facts of this case. At issue is the basic right to group legal action, a right first asserted in this Court by an association of Negroes seeking the protection of freedoms guaranteed by the Constitution. The common thread running through our decisions in NAACP v. Button, Trainmen, and United Mine Workers is that collective activity undertaken to obtain meaningful access to the courts is a fundamental right within the protection of the First Amendment. However, that right would be a hollow promise if courts could deny associations of workers or *586others the means of enabling their members to meet the costs of legal representation. That was the holding in United Mine Workers, Trainmen, and NAACP v. Button. The injunction in the present case cannot stand in the face of these prior decisions.
Reversed.
Mr. Justice Stewart took no part in the decision of this case.
On January 1, 1969, after the decree was entered in the court below, the Brotherhood of Railroad Trainmen merged into a newly created union, the United Transportation Union. The successor union is the petitioner in this case.
35 Stat. 65, as amended, 45 U. S. C. §§ 51-60.
Section 750.410, Mich. Comp. Laws (1948), in relevant part provides:
“Any person ... or organization of any kind, either incorporated or unincorporated . . . who shall directly or indirectly . . . solicit any person injured as the result of an accident ... for the purpose of representing such person in making claim for damages . . . shall be guilty of a misdemeanor . . . .”
The decree entered by the Michigan trial court permanently restrained and enjoined the Union:
“from giving or furnishing legal advice to its members or their families; from informing any lawyer or lawyers that an accident has been suffered by a member or non-member of the said Brotherhood and furnishing the name and address of-such injured or deceased person for the purpose of obtaining legal employment for any lawyer; from stating or suggesting that a recommended lawyer will defray expenses of any kind or make advances for any purpose to such injured persons or their families pending settlement of their claim; from controlling, directly or indirectly, the fees charged or *580to be charged by any lawyer; from accepting or receiving compensation of any kind, directly or indirectly, for the solicitation of legal employment for any lawyer, whether by way of salary, commission or otherwise; from sharing in any manner in the legal fees of any lawyer or countenancing the splitting of or sharing in such fees with any layman or lay agency; and from sharing in any recovery for personal injury or death by gift, assignment or otherwise.”
383 Mich. 201, 174 N. W. 2d 811.
The decree overturned in United Mine Workers also enjoined the union from: “Giving legal counsel and advice.” 389 U. S., at 218 n. 1. It was conceded in that case that the provision was directed at the Union’s employment of an attorney.
Our Brother HarlaN suggests that the injured member should be free to direct the collected information to whatever lawyer he chooses, rather than for the Union to give it to the Union’s recommended legal counsel. However, the injunction prohibits the Union from furnishing the information to “any lawyer,” apparently including both recommended and nonrecommended counsel alike. The injunction would prohibit the injured member’s attorney, regardless of whether or not he was recommended by the Union, from communicating with the Union’s representative who investigated the accident, is familiar with the facts, and, other than the injured member himself, is probably the person most qualified to answer the attorney’s questions and assist in preparation of the claim. To satisfy the Michigan court’s notion that direct communication between the Union and the member's attorney is somehow unlawful, it seems our Brother HarlaN would restrict the Union’s efforts, which we expressly approved in Trainmen, of assisting the injured member in preparing his case for trial, to a written accident report filed with the injured member.
Mr. Justice Brandéis dissented on the ground that this principle should have been applied to strike the other provisions of the injunction as well. 245 U. S., at 263 (Brandeis, J., dissenting).
The injunction also bars the Union “from stating or suggesting that & recommended lawyer will defray expenses of any kind or make advances for any purpose to such injured persons or their families pending settlement of their claim.” The only allegation in the complaint possibly relating to this injunctive provision is that the Union representatives informed the injured members that the 25% fee included all expenses. This provision of the injunction, therefore, is invalid for the same reasons that the provision limiting fees is invalid.