Most places require that you take a course on how to do lead-climbing before allowing you to use the gear. Or they require that you can prove you've already taken such a course.
It's like with diving in that way.

That doesn't mean there's anything stopping you from buying gear and just going out, but I feel like the "proof" would then be that it is broadly expected that you've taken a course and you didn't, which "proves" your lack of knowledge. With this "proof" it would probably be assumed that the accident was user error, rather than faulty equipment.