he's dead. i had to do it. he was gonna hurt my mom." >> reporter: the father is shot because the boy feels his mother's in jeopardy? >> yes. >> reporter: it was getting late on a frigid february night. the deputies put the son and the mother in a patrol car. >> and they asked him where the shotgun was. he told them -- or there was some mention of it bein' in -- in the garage. >> reporter: after securing the weapon, the deputies made their way into the home. on the second floor, in the home office, they found their victim. >> the husband, the father's behind the desk? >> he's behind the desk. the spent shotgun shells are all right there in that doorway area. >> reporter: the detective would quickly learn more about jim tan -- father, husband and businessman. >> he owned his own company. they had lived in canada and then moved to the united states -- some years earlier. >> successful -- >> every day. >> executive, huh? >> by all accounts, yes. >> reporter: but was the successful businessman also an abusive husband? detective peglow looked around the household as crime scene