>> reporter: if it's a good friend, though, who died, is that not possible that someone would have a very hysterical reaction to that? >> you do see strange reactions from 'em, but i believe his reaction was more than overdramatic, would i say. we kept in the back of our heads for later on. >> reporter: both linda and gil told police the affair was now over. but investigators weren't so sure, and began watching them closely. >> there was electronic surveillance in terms of constantly monitoring their phone records, their computer records. and we also had a -- a gps tracker on nunez's car for a while. >> reporter: what were you hoping to find with that? >> we just wanted to determine whether, in fact, they were still together, if they were together at all. >> reporter: it looked like gil and linda were telling the truth. after weeks of watching them, police found no signs they'd been together since tom died. phone records also proved tom