Though then that doesn't explain how there was no blood in the extremely cluttered garage.

It's really aggravating me the way the lack of blood is being treated as some kind of smoking gun and I can explain it.

For one thing, it was a .22 caliber bullet, which is very small. Despite what Avery's lawyers said in the documentary, it doesn't make some kind of explosive splatter on impact like you'd expect with a handgun round (I've shot enough squirrels as a kid with a .22 to remember). It's more like a little puncture wound.

Okay, but what about the exit wound, right? What about when she bleeds out everywhere, right?

Well what kind of criminal mastermind does it take to lay down a goddamn drop cloth first? Or, hell, a three dollar roll of painter's plastic from Wal-mart? It's a junkyard. I'm sure they had plenty of such a thing. Cars get drained of fluids there, they leak when you take them apart, etc.

Say he lays her down on a drop cloth in the garage, stands over her, and shoots her in the head. Entry wound is tiny, blood barely goes anywhere. Exit wound is underneath her head, all spatter goes right on the drop cloth. She bleeds out on the drop cloth. Steven chucks the bullet (maybe after wiping it off) into the garage. Bullet may even have gone wanging off into the garage on its own after striking the floor under Teresa's head (and wouldn't necessarily have penetrated the drop cloth). He rolls Teresa up in the drop cloth, drags her out to the burn pit and sets her on fire.

Boom. Done. No blood. And if he messed up and got a little speck here and there on shit, easily cleaned up. Not five gallons of blood everywhere like if he'd let her bleed out on the concrete.