Bicycle detail

Bike was outside leaning against the retaining wall next to my townhouse in a narrow alley on looker's right where we keep the garbage and recycling bins (right next to an empty recycling bin). Bike was unlocked but not visible from the street since our unit is set back and bike was behind garbage/recycling bins. Bike's chain had dropped off the gears earlier in the week, so it was unrideable. At ~10:20am, doorbell camera caught a white male with grey hair wearing a black hooded sweatshirt wheeling the bike forward, mounting it, and coasting down our driveway. Chain appeared to still be hanging loose.