Opinion by
Mr. Justice Allen M. Stearne,The allocatur is from the Superior Court which affirmed convictions and sentences of the Court of Quarter Sessions of Westmoreland County.
Harry W. Truitt, Jr., John F. Allen, Lester Peay, and Charles B. Tarpley were indicted charged with (1) obstructing an officer in attempting to make an arrest, and (2) assaulting and beating an officer. The jury found all of the defendants guilty and each, except Tarpley (whose sentence was deferred because of illness) was sentenced to one year in the Allegheny County Workhouse. The same four defendants were also indicted charged with (1) assault and battery, and (2) aggravated assault and battery upon the person of John Bordonaro, who was Captain of Police in the City of New Kensington, Westmoreland County. They were all found guilty as indicted, by the jury, and each, except Tarpley, was sentenced to the Allegheny County Workhouse for three years. Robert T. Smith and Charles Tarpley were also indicted for affray, and were found guilty. Smith was sentenced on this conviction for a term of not less than one and one-half years, and not more than three years. The appeals are by Truitt, Allen, Peay, and Smith.
Appellants do not question the sufficiency of the evidence to sustain the verdicts. Their appeals relate to the refusal of the court below to grant a new trial. The questions presented are based upon (1) the admission of allegedly prejudicial evidence concerning communistic connections and activities of Truitt and Smith; (2) the failure of the trial judge to charge on Truitt’s constitutional right of immunity from search *75and seizure by an officer attempting to make an arrest without a warrant in Truitt’s home; (3) the refusal of the motion of counsel for appellants to withdraw a juror when it was shown during the trial that a woman juror had been driven home the preceding day by the alderman before whom the defendants’ preliminary hearing was held.
The Eagle Clothing Company store in New Kensington was being picketed because of a strike against the Ellay Company of New York City, a wholesale clothing company. Employes of Ellay were represented by local 65 of the Wholesale and Warehouse Workers Union. No labor dispute existed with Eagle’s employes. Defendant Smith, who was not a member of Local 65, was sent by that Union from New York to New Kensington as strike leader. In Pittsburgh he hired defendants Peay and Tarpley and also other male and female pickets. Defendant Truitt is a dental technician, whose office and apartment are near the Eagle store. Officials of Local 65 had directed Smith to contact Truitt. All the pickets, including defendants, used Truitt’s office and apartment for their personal convenience.
On Saturday night March 18, 1950, at about 8:30, in front of the picketed store, in the center of town, at the height of the town’s shopping hours, a customer of the Eagle store, John Fee, was, according to the testimony produced by the Commonwealth, attacked and beaten by Smith and other pickets while he was leaving the store after having made a purchase. All of defendants were involved. A friend of Fee came to his rescue. A general fight or fray ensued, in which many people engaged. A large crowd gathered. Police rushed to the scene. Police Captain Bordonaro observed Smith running away. Smith was followed by the Captain and was seen entering defendant Truitt’s apartment through the rear entrance.
*76What thereafter immediately happened is summarized by President Judge Rhodes in his opinion: “Bordonaro returned to the scene to procure the assistance of another officer. Thereafter he went up the front stairs to Truitt’s office on the second floor of the building while the other officer watched the rear entrance. Bordonaro met Truitt, Allen, and Peay coming down the steps. He demanded that Truitt surrender Smith but was told by Truitt that there was no one there. Bordonaro went to Truitt’s apartment on the third floor in his search for Smith. As he came down Bordonaro met Truitt, Allen, and Peay on the second floor landing. Bordonaro again demanded that Truitt surrender Smith. According to Bordonaro, Truitt replied: ‘Get out of here. You ain’t got no business in here. You ain’t getting any fellow.’ Truitt, Allen, Peay, and Tarpley attacked the officer. Someone hit him in the back as he attempted to use the telephone. Truitt took hold of Bordonaro and forcibly removed the telephone from his hands. In doing so, Bordonaro’s arm hit'the door and his wrist was severely injured. Truitt thereupon said to Bordonaro: ‘Don’t make me laugh; you’re not taking that fellow out of here anyhow.’ Peay grabbed Bordonaro and ripped his coat. Bordonaro then informed Truitt, Allen, and Peay that they were under arrest; he succeeded in getting Allen and Peay downstairs where they were turned over to other police. Truitt returned to his apartment. He was later arrested by other officers.”
Defendants, in some particulars, contradicted various statements of some of the Commonwealth’s witnesses relating to the assault and battery upon the Police Captain and to the obstruction in the arrests. They sought to minimize the Police Captain’s painful injuries, torn clothing, and the mauling to which he was subjected. However, in essential features, the *77charges in the indictments were amply and sufficiently established.
The chief complaint of defendants is that the court below erred in refusing to grant a new trial because of the injection into the case of incompetent and irrelevant testimony concerning' communist connections and activities of defendant Truitt and Smith. It is charged that this is a collateral issue, and had nothing to do with the crimes charged for which defendants were indicted, and should not have been permitted in the record; that the effect of such innuendoes, inferences and unsupported irrelevant accusations created prejudice and antagonism against defendants in the minds of the jury.
The trial judge in his charge said: “At this stage I want to say to you that these men are not being tried for being communists. It is your duty and mine and that of the Commonwealth, regardless of what we may think of their beliefs, to give them a fair and a just trial, under the laws of the United States and the Commonwealth of Pennsylvania, and in doing that, you are° to take the testimony in its entirety and decide fairly and reasonably whether these men are guilty of committing an affray and an assault and battery or whether or not they are guilty of resisting an officer, in obstructing him in the service of process.”
The Commonwealth contends that even if such testimony was unsupported and irrelevant, nevertheless, defendants’ able and experienced counsel without objection permitted such testimony to be given. The Superior Court decided, in such circumstances, that the testimony was properly admitted. President Judge Bhodes said: “Appellants elected to try their case with the communist issue injected into it, and we cannot say they did not have a purpose in doing so. Evidence introduced by the Commonwealth, without objection, established that Local 65, which conducted the picketing *78at the New Kensington store, was communist dominated and had been thrown out of the C. I. O. for that reason. The cross-examination of Truitt and Smith as to the character of Local 65 and their connection with it was proper. Likewise, without objection, Truitt and Smith were cross-examined as to whether they were Communists or had any affiliations with the party. Smith had been hired by Local 65 as the picket captain; he brought the pickets to New Kensington on behalf of that organization, and he met Truitt the same day. Truitt knew the officers of Local 65, and was contacted by its organizer from New York relative to the picketing. Appellants met this subsidiary issue and presented testimony in contradiction of the testimony of Commonwealth’s rebuttal witness Cvetic. It was relevant for the Commonwealth to disclose fully the circumstances surrounding the commission of the crimes with which appellants were charged and on trial. It was permissible for the Commonwealth to show Truitt’s relations with Smith and the pickets generally and with Local 65. This evidence had a bearing on whether Truitt harbored Smith at the time Smith'was sought by “the police, and as to whether Truitt did commit the offenses of resisting arrest and assaulting an officer. The testimony as to the communistic character of Local 65 and the communistic connections and activities of appellants relates to an issue in which the appellants had tacitly acquiesced. The evidence as to communism was in the case for all purposes for which it was relevant, and this applies to Cvetic’s testimony introduced by the Commonwealth in rebuttal. See Com. v. Albert, 169 Pa. Superior Ct. 318, 82 A. 2d 695. The evidence relating to appellants’ alleged communistic connections was certainly admissible also to show appellants’ motive in committing the offenses with which they were charged. Cf. Com. v. Campolla, 28 Pa. Superior Ct. 379; Hester v. Com., 85 Pa. 139, 156. Proof of *79motive in the commission of crimes is not always necessary, but such proof is always relevant. Com. v. De Petro, 350 Pa. 567, 572, 39 A. 2d 838. It is therefore not necessary to consider whether the evidence relating to communism was properly limited by the trial judge to its effect solely as impeaching evidence within the rule set forth in Herr v. Erb, 163 Pa. Superior Ct. 430, 433, 435, 62 A. 2d 75, and Com. v. Blose, 160 Pa. Superior Ct. 165, 50 A. 2d 742.”
With this we are unable to agree. Charges may not be established through innuendo, inference or unsupported irrelevant accusations: Schlesinger Petition, 367 Pa. 476, 81 A. 2d 316; Milasinovich v. The Serbian Progressive Club, Inc., 369 Pa. 26, 84 A. 2d 571. True the Eagle Store manager was permitted to testify without objection that Local Union 65 was “thrown out of the C. I. O. because they are communist dominated”. Such a statement, unsupported, by an obviously incompetent witness, is but hearsay. It possesses nó probative or relevant value whatsoever. Whether Local 65 is in fact communist dominated was, therefore, a collateral issue in this case.
Defendant Truitt, without objection, was cross-examined concerning his membership in the Progressive Party, and whether or not such political party was “dominated by communists”. Here again, such testimony was without the slightest probative or relevant value. If it had been objected to it ought to have been, excluded. Defendant Smith was cross-examined about the communist influence in Local No. 65, although he was not a member of it. Smith was also questioned whether or not certain named officers of the Union had been cited by the United States Congress “for communistic activities”. Counsel for defendant then objected in the following language: “By Mr. McKague: Now if the court please, something tells me this is the time to object to this going into the stuff that Mr. Loughran *80is trying to inject into this case for the purpose of prejudicing these defendants.” The objection was overruled and the cross-examination proceeded concerning the communist activities of Local 65 and of the witness. Both defendants Truitt and Smith denied that they were communists. In rebuttal the Commonwealth offered the testimony of Matt Cvetic, who styled himself “an undercover agent with the Federal Bureau of Investigation”. His testimony was offered to attack the credibility of defendant Truitt’s testimony when he denied that he was a communist. An objection was then entered by the attorney for defendants, which was overruled and an exception allowed. The witness was permitted to testify that Truitt was an active communist, and gave testimony concerning Truitt’s communist activities. This was clearly error. Truitt’s testimony, on cross-examination, that he was not a communist was obviously upon a collateral matter. A witness cannot be contradicted on collateral matters to test credibility: Hester v. The Commonwealth, 85 Pa. 139; Commonwealth v. Petrillo, 341 Pa. 209, 19 A. 2d 288.
We agree that counsel may not permit the admission of irrelevant testimony, without objection, and if the case should be decided adversely, then to secure a. new trial upon the ground of fundamental error. In homicide cases, where a defendant’s life may be in jeopardy because of the failure of counsel to perform his duty, the court, impelled by the gravity of defendant’s situation, will examine into the record and ascertain if the trial was free from error: Commonwealth v. Scott, 284 Pa. 159, 162, 130 A. 317; Commonwealth v. Corrie, 302 Pa. 431, 436, 153 A. 743; Commonwealth v. Stowers, 363 Pa. 435, 437, 70 A. 2d 226. Whether defendants, or any of them, are members of the communist party or adhere to its doctrines is a matter entirely foreign to the issue of guilt or innocence on a charge of affray, assault and battery and obstructing an of*81ficer while attempting to make an arrest. Nor is such evidence relevant to indicate motive, and to rebut defendants’ contention that they were engaged in a bona fide labor dispute. Even a bona fide labor dispute would not justify the conduct of defendants in assaulting an officer, obstructing an officer in attempting to make an arrest and in engaging in an affray. Such evidence is collateral and has no place in this case. In I Wig-more, Evidence, see. 57, p. 454, it is stated: “. . . a doctrine of Auxiliary Policy . . . operates to exclude what is relevant, — the policy of avoiding the uncontrollable and undue prejudice, and possible unjust condemnation, which such evidence might induce: . . .”
And, on page 456: “The deep tendency of human nature to punish, not because our victim is guilty this time, but because he is a bad man and may as well be condemned now that he is caught, is a tendency which cannot fail to operate with any jury, in or out of Court.”
We are aware that judicial notice is taken that the communist party is a, subversive organization which conspires to teach and advocate the overthrow of the government of the United States by force and violence: Milasinovich v. The Serbian Progressive Club, Inc., supra, and the cases therein cited. There is, however, no competent proof that Local 65 is communistic. There is no proof that Union Local No. 65, and defendants Truitt or Smith, as communists, were guilty of similar crimes in other cases, in a pattern, design or scheme of criminal conduct. In Hester v. The Commonwealth, 85 Pa. 139, a murder case, other crimes by defendants as members of an organization known as the Mollie Maguires, were permitted in order to prove motive. In Commonwealth v. Strantz, 328 Pa. 33, 195 A. 75, evidence of other crimes was held competent to prove a common scheme or plan. See also Commonwealth v. Fugmann, 330 Pa. 4, 198 A. 99; Common*82wealth v. Kluska, 333 Pa. 65, 3 A. 2d 398; Commonwealth v. Darcy, 362 Pa. 259, 66 A. 2d 663.
The defendants’ contention that it was fundamental error for the trial judge to fail to charge the jury upon the constitutional guarantee against the search of defendant Truitt’s home in attempting to make an arrest without a warrant, was not raised at the trial and therefore need not be considered in this opinion. We also agree that the question of whether or not a juror was guilty of misconduct in driving home after adjournment of the court in the automobile of the aider-man who acted as committing magistrate, is a matter of the exercise of discretion by the trial judge. Under the circumstances in this case, we are not convinced that it was error for the trial judge to refuse a motion to declare a mistrial merely because there was opportunity to influence such juror: 23 C. J. S. sec. 1447, p. 1179; Commonwealth v. Craven, 138 Pa. Superior Ct. 436, 447, 11 A. 2d 191, 196.
The judgments are reversed, the sentences vacated, and a new trial ordered.