On March 22, in the broad daylight of a typically gorgeous day in Beverly Hills, thieves in hoodies and sunglasses took a sledgehammer to the plate glass window of Peter Sedghi’s boutique and furiously rummaged through the shards. In less than 90 seconds, the robbers stole more than $3 million worth of jewels. Two days later, in response to a wave of high-end robberies, the Los Angeles Police Department announced there would be no arrests. Instead, it cautioned Hollywood residents not to wear high quality jewelry in public. “Beverly Hills is one of the most affluent, safest neighborhoods in the...