An aggressive law enforcement probe of an Apple iPhone prototype that reportedly was forgotten by a company employee at a California bar was sparked by a complaint from an O'Melveny & Myers attorney that it had been stolen.

“They said there was a belief that this had been stolen and we want to make sure it’s investigated, and we agreed,” San Mateo County Chief Deputy District Attorney Stephen Wagstaffe tells Bloomberg. “It was reported as stolen property.”

Investigators executed a controversial search warrant last week on the home of a Gizmodo editor, seizing several computers and other material. The gadget site reportedly paid the finder of the lost phone $5,000 in order to examine it and publicly post photos of the device before returning it to Apple.

Although Gawker Media, which owns the site, has contended that the search was illegal under reporter shield laws, Wagstaffe told CNET News yesterday that prosecutors carefully considered the issue before proceeding with what they believe to have been an appropriate approach.

"I think the people who are saying, 'No, we should have waited' and did it the other way first don't understand that in the world when you're investigating crimes, evidence sometimes gets deleted and destroyed," he says. "If you sit there and work by the Marquess of Queensberry rules, then bad guys win."

Related coverage:

Threat Level (Wired): "iPhone Finder Regrets His ‘Mistake’"