Bob Koscik gets onto his hands and knees and crawls under a fallen tree. He turns and watches as his daughter, Eva Berk, scrambles onto a log and then leaps down onto the back of another downed log.

Around 3 a.m. July 18, 2009, Robert Liebler's boots crunched in the desert sand on the mountainside just above the Palm Springs Art Museum. Alongside colleague Veit Elser, the two longtime college ...