Rockefeller impersonator convicted of murder in California April 10, 2013 -- Updated 1842 GMT (0242 HKT) (CNN) -- A German-born man known for impersonating a Rockefeller was convicted of first-degree murder Wednesday in the death of his landlady's son in California. A California jury found Christian Karl Gerhartsreiter guilty of killing John Sohus, who disappeared at age 27 in 1985. Sohus' dismembered remains were found in 1994 by workers installing a pool at a home his mother once owned in San Marino, California. At the time of Sohus' disappearance, Gerhartsreiter had been renting a guesthouse from Sohus' mother, authorities said. Gerhartsreiter led a life of multiple identities, at one point assuming the identity of "Clark Rockefeller," a cultured poseur who never seemed to have a job. A Boston tabloid dubbed him "Crockefeller." A 2010 made-for-TV movie, "Who Is Clark Rockefeller?" starring Eric McCormack as Gerhartsreiter, aired on the Lifetime network. Last year, he was serving a prison sentence in Massachusetts for kidnapping his then-7-year-old daughter from his ex-wife in 2008 when he was transferred to California to face charges in the Sohus case.