Why can’t old ladies deny the Holocaust if they want to?

The following quote is from this news article: https://www.usatoday.com/story/news/world/2018/05/08/nazi-grandma-ursula-haverbeck-who-denies-holocaust-taken-jail/589613002/

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Serial Holocaust denier

During her trial, [Ursula] Haverbeck spoke of an “Auschwitz lie,” claiming it was not an extermination camp, but merely a labor camp. [I believe that Ursula is correct.]

She and her late husband Werner Georg Haverbeck, who was an active member of the Nazi party, founded a right-wing education center called Collegium Humanum. The center was banned in 2008.

Haverbeck also wrote for the right-wing magazine Stimme des Reiches (Voice of the Empire). She used the magazine to express her views that the Holocaust never took place. [I believe that she is correct.]

Under German law, denying the Holocaust constitutes incitement to hatred and can carry a prison sentence of up to five years.

This article was originally published on DW.com. Its content is created separately from USA TODAY.

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I believe that having an opinion does not make one a criminal.