Solution
Donuts O’ Sizzlin’
Two clues to find in today’s 5 minute mystery…
Jasper said he didn’t hear anything because he was frying Donuts in the front, however he also said he over heard his uncle’s phone call. He couldn’t both not-hear and hear. That’s the first clue.
Even if Jasper did somehow overhear the phone call, Jeffrey never mentioned Constable Ken by name so Jasper couldn’t have known that Constable Ken was on his way as he claimed, and that’s the second clue.
Jasper had implicated himself, and Field-Marshal Mogau knew it!