San Francisco Mayor Gavin Newsom is expected to testify Tuesday morning in the trial of a former city network engineer accused of refusing to hand over passwords to the city's main computer network in 2008.

Terry Childs, now 45, has been in custody on $5 million bail since July 2008, when prosecutors accused him of hijacking the city's new FiberWAN network, which he had been in charge of implementing as a lead engineer for the San Francisco Department of Technology.