deprogram and delegitimize

[kjc0123]

What's the meaning of "deprogram" and "delegitimize" in the following sentence?

Hundreds of members of the Unification Church who were caught and harangued by so-called deprogrammers complained of interrogation technique similar to that reported during the European witchhunts.

Deprogrammers would tell the detainee that he had been "brainwashed" by the "cult" and threaten to hold him indefinitely unless he "realized" he had been brainwashed. Opponents of deprogramming claim that this parallels the tactic of accusing a prisoner of witchcraft and torturing them until they "confess" to witchcraft. Jeremiah Gutman, a lawyer with the ACLU, chronicled several hundred such cases in the U.S. before deprogramming as "therapy" was delegitimized there.

[bernardo]

To deprogramme means to teach somebody an alternative opinion - a different opinion from the one which they are familiar with.  For example, a person who has escaped from North Korea to South Korea (or to Japan) would be deprogrammed in order to teach them about the errors and failures of communism.  It is the opposite of "to programme", which is a bit like "to indoctrinate", to feed somebody with propaganda.

To delegitimize means that something is no longer regarded as acceptable or "legitimate".

The methods used by the deprogrammers (teachers) came to be delegitimized (seen as unfair or unacceptable).