in yolo county, it's ed prieto.you do background checks on the forensic pathologists who co to work here? >> we a background investigation to make sure for criminal activity... if they've been involved in any criminal activity. we make sure that their... their... their qualifitate... qualifications or certifications are valid, that they come with some reference. so, yes, we do... we do that. >> bergman: because we got the name of dr. gill, and he's had serious problems all over the united states. >> oh, really? >> bergman: and in 2006, out of a case that he was involved in in sonoma county, the state bar concluded... well, they have a whole chapter here. i can give it to you. it says "incompetent pathologist." >> huh. news to me. i did not know that. and i think you've alerted me to something that i... again, i always depend on the experts, and sometimes the experts don't really give you the right information. so i think this is really... have alerted me to look into this a little bit further. >> bergman: after that