happened. and she didn't ask anything else. >> reporter: that was diana's story. she hired her shooting instructor to intimidate greg, but that was it. so now police had another suspect, weldon mcdavid. his wife, lea, was home with her newborn baby when the phone rang. >> and i answered the phone. it was s.w.a.t. they were on my street. and they told me to come out of the house with the baby. >> reporter: did you have any clue why they were there? >> no. >> reporter: they were there to look for evidence that weldon shot greg mulvihill. >> the most striking thing about the house is that mr. mcdavid had guns everywhere. >> reporter: san diego county deputy district attorney jodi white breton said they found a number of guns in the house. but none was connected to the crime. but then, hidden in the garage -- >> they found the upper portion of an ar-15. >> reporter: police noticed that there was a suppressor or silencer attached to the weapon