ROME (Reuters) - A Rome university professor was acquitted on Wednesday of slandering Agriculture Minister Francesco Lollobrigida for comparing him to a Nazi governor.

A judge kicked out the case against Donatella Di Cesare, a professor of philosophy at the Sapienza University in Rome, saying "the fact does not constitute a crime".

"This is a great victory for democracy and free debate. Critical voices must be heard," Di Cesare wrote on X.

Lollobrigida, who is the brother-in-law of Prime Minister Giorgia Meloni, made no immediate comment.

He launched his legal case last year after Di Cesare appeared on a television chat show and criticised him for saying that Italy was at risk "of ethnic replacement" because of its low birthrate.

Cesare said he used language similar to that of a "Gauleiter" -- a regional leader of Adolf Hitler's Nazi party.

In his suit, Lollobrigida accused her of portraying him as a Nazi "who glorifies concentration camps". Cesare defended herself in the Italian press, saying she had compared his choice of words to that of a Nazi, but had not called him one.

The defamation case against Cesare was one of a number of legal suits brought by government politicians against outspoken critics in recent months. Opponents say it is a concerted effort to limit freedom of speech, something ministers have denied.

(Reporting by Crispian Balmer; Editing by Keith Weir)