[rellimpank]

--carjacking could be completely eliminated by simply putting out a few decoys, in the form of expensive vehicles with a policewoman disguised as a suburban "mom", with the back seat containing two officers with shotguns at the ready, using them on any would-be carjacker as he approached the vehicle---

--obviously this wouldn't pass the "political correctness" test , however--

[BipolarBob]

Why spring for the manpower costs? Set it like a mousetrap and have springloaded seats that impale carjackers. Clean the seats and reset the trap.