From the police blotter, Fremont, California, January 8, 2013:

IH # 13002139 Suspicious Circumstance 

At approximately 4:25 a.m., witnesses called to report a suspicious male running through the parking lot of Lucky's on the 38400 block of Mowry Ave. They initially described him as a male not wearing pants or possibly just underpants and wearing a "Scooby Doo" or bear type head mask. Officer Sanchez and Officer Gilfoy arrive shortly after and contact a 47 year old adult male behind the Huddle who was in fact, wearing a "Scooby Doo" head mask, dog leash and light colored pants. He stated that he had recently lost weight and wanted to show off his new body. The subject was released.

This is the sort of thing you'd expect from Fred, not Scooby.

Although, come to think of it, when they all gathered to pull off his mask and dramatically reveal his identity, as I'm sure they did, maybe it turned out to be Fred after all.