May an endorser who passes a bad check may be held liable under BP 22?

Yes. An endorser who passes a bad check may be held liable under BP 22, even though the presumption of knowledge does not apply to him, if there is evidence that at the time of endorsement, he was aware of the insufficiency of funds. It is evident from the foregoing deliberations that the presumption in Sec. 2 was intended to facilitate proof of knowledge and not to foreclose admissibility of other evidence that may also prove such knowledge. Thus, the only consequence of the failure to present the check for payment within ninety (90) days from the date stated is that there arises no prima facie presumption of knowledge of insufficiency of funds. But the prosecution may still prove such knowledge through other evidence. Whether such evidence is sufficient to sustain probable cause to file the information is addressed to the sound discretion of the City Prosecutor and is a matter not controllable by certiorari. Certainly, petitioner is not left in a lurch as the prosecution must prove knowledge without the benefit of the presumption, and she may present whatever defenses are available to her in the course of the trial. (Bautista vs. CA G.R. No. 143375. July 6, 2001)