[naavis]

In many parts of the world it is illegal for a recruiting party to search for information on a candidate without their consent.

[JSteph22]

Whichever parts of the world that may be, you can guarantee that it happens anyways.

Unenforceable rules are never followed.

[Tepix]

What are laws that prohibit it?

[naavis]

One example is Finnish legislation: https://finlex.fi/fi/laki/ajantasa/2004/20040759#L2P4 Sadly only available in Finnish. The law applies both to employees and candidates.

EDIT: Looks like there is an English translation. See section 4 of: https://finlex.fi/en/laki/kaannokset/2004/en20040759_2019034...