Yeah I mean you pay money and take a little course to become a notary and you have to reup every year (or three years? I can't remember). The point is you take on legal liability. A notary cannot claim, "i didn't realize, I didn't know, I didn't double check." Most of the money you pay is in liability insurance in case you screw up. Because if a notary stamps their name to something false, they bear the legal liability which is enough for a notary to not take the risk of flippantly stamping things that are untrue.

You can also legally marry people.

There are also legal limits to how much you can charge (like 10 bucks and document or something. It's not much). Since each stamp doesn't earn much, but the liability could cost you a lot, it keeps notaries pretty honest. It's a decent system.

Mostly only nerds are notaries anyway, so the promising and putting your name to something does some of the heavy lifting by itself

Anyone could be a notary – you just have to pinky promise that you saw something happen under oath

The notary has to be approved by the State. Basically, if a notary attests to some fact, it is as if the entire government bore witness to it.

You think that someone would break the sacred oath they took to become a notary? What is this world coming to...

Wikipedia does not specify that and I have no clue

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