A Polish prosecutor has questioned a Polish-American scholar, Jan Tomasz Gross, to determine if he committed the crime of publicly insulting the nation with a statement on Polish violence against Jews during World War II.

Gross, a professor based at Princeton University, told The Associated Press he was questioned for five hours Tuesday in Katowice but does not yet know if he will be charged with the alleged offense, which can carry a prison term of up to three years.

Poland’s case against Gross, which also involves a presidential threat to strip him of a state honor, has raised questions about the conservative leadership’s commitment to the freedom of scholarship. Law and Justice, a conservative and nationalistic party that controls both the presidency and parliament, is also centralizing power in a way that has raised concerns about its commitment to democracy more broadly.

Gross was questioned after multiple complaints were filed with prosecutors by Polish citizens over an article published last year in which Gross said Poles killed more Jews during the German occupation than they killed Germans — a claim that challenges a widespread conviction in Poland that the Polish response to the German terror was almost exclusively honorable.

Gross made the comparison in an article published by Project Syndicate in September critical of how Poland and other Eastern European countries have reacted to the migrant crisis. He decried the region’s opposition to accepting refugees as “heartless” and argued that the attitude is rooted in the region’s “murderous past.”

In the most controversial section, Gross wrote: “Consider the Poles, who, deservedly proud of their society’s anti-Nazi resistance, actually killed more Jews than Germans during the war.”

The prosecutor’s office told the AP that it could not divulge what was said during the questioning, citing the secrecy of the investigation. However, Gross said he was asked to provide information backing up that historical assertion and was also asked if he had intended to incite Poles.

“I told him straight that I was not trying to incite the Polish nation. I was trying to raise awareness about the problem of refugees in Europe,” he said. “I am just telling the truth and the truth sometimes has a shocking effect on people who are not aware of what the truth is.”

Jacek Leociak, a historian with the Polish Center for Holocaust Research, said it is difficult to establish exactly how many Jews were killed by Poles during the war but that the number is significant.

“The claim that Poles killed more Jews than Germans could be really right – and this is shocking news for the traditional thinking about Polish heroism during the war,” he said. He said Gross’s comparison has merit because it “reveals this dimension of the Polish war experience which was always covered, hidden and suppressed.”

President Andrzej Duda is considering stripping Gross of an Order of Merit he received in 1996. His spokesman, Marek Magierowski, said Wednesday that the president has not yet decided.

(AP)