A former San Marino, Calif., police officer testified today in the murder trial of Christian Karl Gerhartsreiter that a neighbor reported seeing Gerhartsreiter digging in the back yard where the remains of John Sohus would be found years later. Another witness said Gerhartsreiter invited her over for a game of “Trivial Pursuit” in the yard and she noticed that someone had been digging. She said she asked Gerhartsreiter about it — and he told her he had been having plumbing problems.