(dissenting, with whom Lynch, J., joins). Because I do not agree that there was sufficient evidence to permit a rational juror to find beyond a reasonable doubt that the defendant violated clause (c) of the injunction, and because the jury instructions defining the key terms of the injunction allowed the jury to convict the defendant for both constitutionally protected and unprotected activities, I dissent.
1. Sufficiency of the evidence. The majority affirms the denial of the defendant’s motion for a required finding of not guilty because it concludes that “a rational trier of fact could properly draw the inference that the defendant directed, instructed, conspired with, aided or abetted persons engaging in acts described in clause (a) or (b) of the injunction.” Ante *358at 355. A careful review of the evidence at trial, however, reveals that the evidence is insufficient to sustain the defendant’s conviction, especially in light of the fact that the defendant’s actions occurred during the course of a political demonstration.
In reviewing the denial of a motion for a required finding of not guilty, we consider whether the evidence, taken in the light most favorable to the Commonwealth, is sufficient to permit the jury to infer the existence of the essential elements of the crime charged. Commonwealth v. Latimore, 378 Mass. 671, 676-677 (1979). To sustain the denial of such a motion, “it is not enough for the appellate court to find that there was some record evidence, however slight, to support each essential element of the offense; it must find that there was enough evidence that could have satisfied a rational trier of fact of each such element beyond a reasonable doubt” (emphasis added). Id. at 677-678.
To support its contention that there was sufficient evidence to sustain the defendant’s conviction, the Commonwealth relies on the following evidence: the defendant was present at the demonstration; he associated with “known leaders of Operation Rescue” and “known antiabortion demonstrators”; he spoke with several persons who subsequently joined the blockade; and he gestured during the course of the demonstration. Ante at 350, 354-355. Much of this evidence, however, was not probative on the issue whether the defendant violated the injunction, and would not permit a rational trier of fact to infer that the defendant directed, instructed, conspired with, aided, or abetted persons engaging in acts described in clause (a) or (b) of the injunction.
First, the mere fact that the defendant was present at the demonstration does not justify the inference that the defendant assisted others in violating the injunction.1 Second, the fact that the defendant spoke with “known leaders of Opera*359tian Rescue” and “known antiabortion demonstrators” also does not help the Commonwealth’s case. In order to prove that the defendant violated clause (c) of the injunction, the Commonwealth must prove that a person or an organization violated clause (a) or (b) of the injunction. See Planned Parenthood League of Mass., Inc. v. Blake, 417 Mass. 467, 481, cert. denied, 115 S. Ct. 188 (1994). There was no evidence to suggest, however, that either the “known leaders of Operation Rescue” or the “known antiabortion demonstrators” with whom the defendant spoke, violated or attempted to violate the injunction. Thus, evidence of the defendant’s association with these individuals was not relevant to the issue whether the defendant violated clause (c) of the injunction. Further, the Commonwealth’s repeated references to the defendant’s association with these individuals was highly inflammatory as it contributed to the likelihood that the jury would find the defendant guilty by association.
The Commonwealth also relies on evidence that the defendant spoke with several persons who joined the blockade after having spoken with him. The Commonwealth offered no evidence, however, as to the content of these conversations, and none of these individuals was arrested or charged with violating the injunction. Even if the jury could have found that the defendant associated with persons who subsequently joined the blockade, this alone does not justify an inference that he assisted in the commission of the crime. Post hoc, non ergo propter hoc. See Commonwealth v. Perry, 357 Mass. 149, 151 (1970); Commonwealth v. Fancy, 349 Mass. 196, 200 (1965). “A contrary holding would be tantamount to introducing into our law a doctrine of guilty by association . . . .” Id. See also NAACP v. Claiborne Hardware Co., 458 U.S. 886, 908 (1982) (“[t]he right to associate does not lose all constitutional protection merely because some members of the group may have participated in conduct . . . that itself is not protected”).
Thus, we are left with the core evidence on which the Commonwealth primarily relies: the fact that the defendant made gestures which police interpreted as “directing” others *360to join the blockade. These gestures, consisting of pointing to empty spots in the blockade and grabbing an individual by the sleeve of his shirt, are commonplace actions which, in the course of a political demonstration, are ambiguous and inconclusive in nature. See Commonwealth v. Saez, 21 Mass. App. Ct. 408, 412 (1986) (defendant’s actions of looking up and down street insufficient to prove he acted as lookout). This evidence could only leave to surmise and conjecture the content of the defendant’s words, the significance of the defendant’s actions, and the intent of the defendant to assist others in violating clause (a) or (b) of the injunction. See Commonwealth v. Fancy, supra.
In the context of a political demonstration, we must carefully balance the rights of persons seeking abortions with the rights of persons protesting against laws which they believe are morally wrong. Unfortunately, today’s decision will undeniably chill the free expression of lawful protesters by sending a clear message that even the most commonplace actions during the course of a demonstration may suffice to sustain a conviction for criminal contempt. Lawful protesters will be deterred from participating in peaceful demonstrations for fear that seemingly innocuous actions may be misconstrued as violative of clause (c) of the injunction. On this record, the evidence is insufficient as a matter of law.
2. Jury instructions. Even assuming that there was no error in the denial of the defendant’s motion for a required finding of not guilty, the defendant’s conviction still should be reversed. The jury instructions defining key terms of the injunction, such as “directing,” “instructing,” and “aiding or abetting,” were so broad that the jury could have convicted the defendant for constitutionally protected activities.2
*361Although some of the language which the judge used to define the injunction’s terms properly limited the scope of the injunction, other language permitted the jury to convict the defendant for activities which clearly fall within the protection of the First Amendment to the United States Constitution.3 For instance, the judge’s charge defining the term “instructing,” allowed the jury to convict the defendant not only for “ordering” others to engage in the prohibited activity, but also for “conveying information” to those individuals.4 Clearly, this instruction burdens protected speech. Only if the information conveyed by the defendant is likely to incite another to engage in imminent lawless action may it be proscribed. See Brandenburg v. Ohio, 395 U.S. 444, 447-448 (1969) (per curiam) (mere abstract advocacy of unlawful conduct may not be prohibited).5 The judge’s instruction, *362however, did not inform the jury of this limitation.6 Thus, under this instruction, the jury could have found the defendant guilty of criminal contempt for merely conversing with others who participated in the blockade.7
The judge’s instruction defining “aiding or abetting” further contributed to the likelihood that the jury would convict the defendant for protected activities. The judge informed the jury that the assistance required for “aiding or abetting” “may take the form of . . . encouraging the other person to engage in the act.” Numerous activities could have been construed by the jury as “encouraging” other persons to engage in the blockade. Protected activities such as singing, chanting, picketing, or merely showing up in support of those who chose to further their cause through civil disobedience, could have fallen within the instruction’s proscriptions.
The Supreme Court of the United States has consistently held that, where the instructions and evidence indicate the possibility that a defendant was convicted for constitutionally protected activities, that conviction must be reversed. Stromberg v. California, 283 U.S. 359, 369 (1931). “If, *363under the instructions to the jury, one way of committing the offense charged is to perform an act protected by the Constitution ... a general verdict of guilt [must] be set aside even if the defendant’s unprotected conduct, considered separately, would support the verdict.” Zant v. Stephens, 462 U.S. 862, 883 (1983). In Street v. New York, 394 U.S. 576, 578 (1969), the defendant was convicted under a New York statute which prohibited publicly defying or casting contempt on the American flag either by words or acts. Because the record indicated that the defendant’s conviction could have been based on his protected words as well as on his arguably unprotected conduct, i.e., flag burning, the Court reversed the defendant’s conviction. Id. at 590, 594.
Similarly, in Thomas v. Collins, 323 U.S. 516, 518 (1945), a labor organizer was adjudged in contempt for violating a restraining order which prohibited him from soliciting new union members without first obtaining an organizer’s card as required by a Texas statute. The order adjudging the defendant in contempt was based both on a speech expressing a general invitation to a group of nonunion workers, which the Court held to be constitutionally protected speech, as well as on the solicitation of a single individual. Id. at 528-529. Because the record showed that the judgment rested both on the defendant’s protected and unprotected conduct, the Court declined to adopt the State’s argument that the judgment could be sustained on the basis of the individual solicitation alone. Id. at 528. “The judgment. . . must be affirmed as to both or as to neither.” Id. at 529.
In Street and Thomas, the judgments rested, in part, on the fact that the defendant had been found guilty based on expressive activity protected by the First Amendment. Likewise, in the present case, the jury could have convicted the defendant based on protected conduct which occurred during the course of a lawful demonstration. There was evidence that the defendant had spoken with several individuals who subsequently joined the blockade. Evidence of these conversations could have supported impermissibly a finding that the defendant “conveyed information” to those who violated the *364injunction. Furthermore, the mere presence of the defendant at the blockade could have been construed as “encouraging” other persons to engage in acts prohibited by clause (a) or (b) of the injunction. Because the judge’s instructions allowed the jury to base their verdict on both protected and unprotected activities, and because it is not clear on which evidence the jury relied, the defendant’s conviction must be reversed.
3. Conclusion. Although I do not suggest that those who violated the injunction should escape proper contempt proceedings, instructions that allow a jury to convict an individual for lawfully and peacefully demonstrating against a particular cause reach too far. Whatever the particular contours of this injunction were intended to be, the instructions defining the terms of the injunction clearly crossed the line and allowed the jury to convict the defendant based on activities which are protected by the First Amendment. As applied, the injunction not only infringes on the defendant’s First Amendment rights, but also chills the free speech of peaceful protesters in the future. I dissent.
Although the defendant was present at the demonstration, at no point did he participate in the blockade. On the contrary, the evidence clearly showed that the defendant remained on the sidelines, lawfully demonstrating with a group of supporters who sang and carried signs.
The majority dismisses this claim by pointing out that clause (c) of the injunction has been held to be constitutional. Ante at 351, 353 n.3. See Planned Parenthood League of Mass., Inc. v. Blake, 417 Mass. 467, cert. denied, 115 S. Ct. 188 (1994). Even if the injunction on its face is constitutional, the instructions defining the proper scope of the injunction still may deprive the defendant of his constitutional rights.
The majority also states that “[t]he judge did not act improperly in defining words used in the injunction.” Ante at 353 n.3. This response also *361fails to address the defendant’s argument. There is no question that the judge was entitled to define the terms of the injunction. What was required, however, was that he define them correctly.
Finally, the majority cites to Madsen v. Women’s Health Ctr., Inc., 114 S. Ct. 2516 (1994), to support its contention that the United States Supreme Court upheld a clause in an injunction which was similar to clause (c). Ante at 353 n.4. Although the injunction at issue in the Madsen case had a clause that prohibited the defendant from “encouraging, inciting, or securing other persons to commit any of the prohibited acts,” id. at 2522, the Court did not consider the constitutionality of this clause. Id. at 2526 n.5. What the Court did consider was a portion of the injunction which prohibited individuals “acting in concert” with those named in the injunction from (1) inhibiting or impeding the ingress or egress of persons into the clinics; and (2) congregating, picketing, or patrolling within thirty-six feet of the property line of the clinic. Id. at 2522, 2530.
It is not enough that some of the language in the instruction properly defined the scope of the injunction. When sanctionable “conduct occurs in the context of constitutionally protected activity . . . ‘precision of regulation’ is demanded.” NAACP v. Claiborne Hardware Co., 458 U.S. 886, 916 (1982), quoting NAACP v. Button, 371 U.S. 415, 438 (1963).
The judge told the jury that “instructing” means “to convey information, to direct, to order, to tell what to do.”
“[T]he mere abstract teaching ... of the moral propriety or even moral necessity for a resort to force and violence, is not the same as preparing a group for violent action and steeling it to such action.” Noto v. United States, 367 U.S. 290, 297-298 (1961). “A statute which fails to draw this distinction impermissibly intrudes upon the freedoms guaranteed by the First and Fourteenth Amendments. It sweeps within its condemnation *362speech which our Constitution has immunized from governmental control.” Brandenburg v. Ohio, 395 U.S. 444, 448 (1969) (per curiam).
Similarly, in defining the term “directing” the judge instructed the jury that the defendant would be in violation of the injunction if he “suggested” that others engage in the prohibited activity. This instruction, without further elucidation, also runs afoul of constitutional requirements. See Brandenburg v. Ohio, supra at 447-448.
This instruction also allowed the jury to convict the defendant for “conveying information” without regard to whether the defendant specifically intended to assist individuals in violating the injunction. To punish association with a group having both legal and illegal aims, there must be clear proof that a defendant specifically intended to accomplish the aims of the organization by unlawful means. See Noto v. United States, supra at 299. “[Tjhis intent must be judged ‘according to the strictest law,’ for ‘otherwise there is a danger that one in sympathy with the legitimate aims of such an organization, but not specifically intending to accomplish them by resort to [unlawful means], might be punished for his adherence to lawful and constitutionally protected purposes, because of other and unprotected purposes which he does not necessarily share.” NAACP v. Claiborne Hardware Co., supra at 919, quoting Noto v. United States, supra at 299-300.