turns out he crossed paths with david strickland before. >> i'd interviewed david strickland in 2012der. >> remember that tip about a white car seen speeding in the park the night of the murder? the tipster was david strickland. >> he came in as a good samaritan wanting to provide information. >> reporter: that meant david strickland lived just blocks from the park where the shootings took place. >> and now here he is being mentioned in connection with a guy who had been mysteriously fingered for the murder? >> that's right. >> so, just like that, basically, mr. melcher is no longer the focus of this, it's now david strickland? >> chris melcher went on to explain that he and strickland were no longer on good terms. he believes strickland had stolen several of his guns so he had strickland arrested. >> the gun robbery put a damper on their relationship. >> strickland pleaded nat guilty to the gun charge and was released soon after. the charges were still pending and vellerman wondered could writing that letter been payback for having him arrested? >> i knew there was bad blood between