It actually had nothing to do with deadlifts or bad form. I was working on my bench press and couldn't get the fifth rep up. I set the bar down on my chest and instead of calling out for help (to any of the fifty people standing nearby), I thought it would be less embarrassing to just roll it down to my knees and then stand up and set the weight down. Stupid decision. Once I got the weight to my knees, I severely underestimated my back-to-chest strength ratio and the weight plummeted to the ground, pulling my (arched) back down with it. I think it was about 215 lbs (97 kg).

The key to deadlifts is good form and not letting your back arch at all. I would recommend getting an expert trainer or an advanced lifter to help you practice your form if you are worried about it. It's worth the time to prevent an injury.

You should really use safeties when bench pressing. I just read about a guy who died doing a bench press when he lost control of the bar and it landed on his neck!

https://stronglifts.com/bench-press/safety/

Man... I feel your pain.. been in the same situation a few times, but why not just shame-roll (drop the bar to one side and just sort of wriggle out from under it on the opposing side)? It sucks but keeps you safe.

not the person you're responding to but a lot of times people have clips on the weights at gyms

I was taught not to use a clamp on the bar when doing bench, so you can lean to one side and let the weights drop off if you get stuck.

Seems like questionable advice - sounds like a great way to accidentally drop a bunch of weights to the floor if you're at all uneven with your bar path (not at all unusual when fatigued).

Not only that, but even a little shift in the weights can cause problems with your lifts. Warmups (135 or so) I'll leave them off, but anything over 200 I'll put them on.

Then you really have to look out for the recoil as the suddenly-unbalanced bar whips around.

Bench press at any significant weight just flat-out isn't safe without a spotter.

My friend was a powerlifter. According to him, back injuries are far more common on the squat than the dead. It's somewhat counter intuitive, but the dead is generally quite safe.

You should always use good form and always have respect for the weights (don't get cocky), but maybe have a bit more respect for the squat :P

I recommend reading Anatomy Without a Scalpel.

DLs are complicated, but you'll see a lot more uniformity when you take your advice from people who are strong themselves.