¶1Opinion by
¶2Clair L. Bollinger was brought to trial in the Court of Quarter Sessions of York County on five bills of indictment, each charging extortion in the first count and cheating by fraudulent pretenses in the second count. The trial covered a period of four days, and there is a voluminous record. In each case the jury returned a verdict of guilty on both counts. Motions by the defendant for a new trial and in arrest of judgment were overruled, and sentences were imposed. These appeals followed.
¶3The record discloses that appellant was the duly authorized constable in and for the Borough of Spring Grove in York County. He was also licensed to conduct a private detective business under The Private *494Detective Act,
¶4It was the theory of the Commonwealth that, in each of the aforesaid cases, appellant submitted bills of costs and received payment for services which he did not perform and to which payment he was not entitled; that this was done (1) wilfully and fraudulently by color of appellant’s public office wherefore he was guilty of extortion; and (2) as a result of false pretenses by virtue of which appellant intended to cheat and defraud the County of York wherefore he was guilty of cheating by fraudulent pretenses. Appellant frankly admitted that, in large part, he had not performed the services personally. He also admitted that *495lie signed the hills of costs in blank, and that they were subsequently filled in by one of the alderman’s secretaries. His theory was that the services were performed by authorized persons acting under his direction, that the fees received were proper in amount, that in no instance was the County of York called upon to make double payment, and that he had no criminal intention for the reasons (a) that the practice which he followed was in accord with the custom which prevailed in York County, and (b) that he had sought advice in connection therewith from several public officials and had at no time been informed that the practice was improper.
¶5We are clearly of the opinion that the instant convictions cannot be sustained because appellant was not permitted to offer testimony in support of his theory. The crimes of extortion and cheating by fraudulent pretenses are proscribed, respectively, by Sections 318 and 836 of The Penal Code
¶6Appellant vigorously denied that he had any criminal intention. He sought to prove that, following the appearance of an article in a local newspaper concerning the custom of one constable serving process and another constable receiving payment therefor, he twice requested of the district attorney “an interpretation and a ruling on this practice”; that he also consulted *496one of the judges; and that both he and Alderman Nickey asked an assistant district attorney “about the legality of such procedure”. Appellant was not informed “why it couldn’t be done”, in fact the assistant district attorney said “something to the effect that, well, this isn’t quite kosher but nothing will be done about it”. The trial judge refused this offer of proof on the ground that “it never was and never can be a defense to any crime that other people also were violating the law”. This is of course true, but it entirely overlooks the purpose of the offer. Appellant did not endeavor to prove the custom as a matter of excuse, but to show that he lacked the requisite criminal intent. A bona fide and reasonable belief in the existence of facts which, if they did exist, would render an act innocent, is a good defense: Commonwealth v. Lefever, 151 Pa. Superior Ct. 351, 30 A. 2d 364.
¶7Appellant was also not permitted to show, with regard to signing bills of costs in blank, that this was the customary practice in the offices of aldermen in York County; and that, with regard to fees charged for mileage, he was complying with the customary practice in the office of the county controller. In our view this testimony was also relevant on the issue of criminal intention, and its exclusion was prejudicial error. “Where, as here, the Commonwealth officers have acted in conformity with a long established local custom, an individual may rest upon the assumption that he will not be covertly prosecuted by such officials for accepting the validity of such custom”: Commonwealth v. Wilson, 158 Pa. Superior Ct. 198, 44 A. 2d 520.
¶8Judgments reversed with a venire.
¶9 Act of August 21, 1953, P. L. 1273, 22 P.S. 11 et seq.
¶10 Act of June 24, 1939, P. L. 872, 18 P.S. §4101 et seq.