The Los Angeles Times:
"The side door of the home in the hills of Encino was unlocked on the Saturday morning in late August. The elderly owners were in a back room, otherwise occupied. The maid had stepped out. So the thief stepped in -- and made quick work of the wealthy real estate investors' multimillion-dollar art collection. Marc Chagall's 'Les Paysans,' gone. Diego Rivera's 'Mexican Peasant,' a blank spot on the wall. Arshile Gorky's 'Cubist Still Life,' ditto. ... By the time the maid returned about an hour later, at least a dozen artworks ... had been stripped from the home. ... The anti-theft system, for whatever reason, did not prevent the heist."
Derek Fincham reviews the four possible reasons for the theft.