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M was standing in for Sergeant Lucas, and had gone to the Rue Montmartre to arrest Oscar Laget on a financial charge. When Lucas had visited earlier, the clerk, Ernest Descharneau, had said he'd be back at 4:00. Just at 4:00, when M and the men from the DPP arrived, there was the sound of a shot, and when they went into Laget's office they found him dead, his gun beside him on the floor, an apparent suicide. Behind a curtain they found Mme Laget, who said she'd just arrived. M is somehow suspicious, and interviews Descharneau, who'd been Laget's superior in the army, but fallen on hard times and wound up the employee of the unscrupulous Laget.
M had felt that the smell of gunpowder in the room hadn't been fresh, and that Laget's body was unnaturally close to the radiator. When he learned that Descharneau had stayed in the office for lunch, and that Laget usually returned at 3:00 and took a nap in his office, and that Descharneau had had a gun shop, he put it all together. Descharneau, hating Laget and fearing that once more he'd evade prosecution, shot him with a silencer on the gun while he was napping, at the time he'd gone out "to answer the phone". When M and the others, as well as Mme Laget had arrived, he'd pressed the call button under his desk, which set off a firecracker in the open window in the hall, sounding like a gunshot, and looking like a suicide. Descharneau denied all, but hung himself in his cell with strips of linen torn from his shirt.
Maigret of the Month: July, 2010