Giovanni Palatucci, who died in the Dachau concentration camp in February 1945, aged 36, was regarded as Italy's answer to Oskar Schindler, the German industrialist who saved thousands of Jewish workers during the Holocaust.
Over the years he was honored by Yad Vashem, Israel's official Holocaust memorial, and declared a martyr by Pope John Paul II, putting him on the path for beatification and sainthood.
But the Centro Primo Levi said fresh research it coordinated revealed that "Palatucci continued to work under the Germans and to provide information on the few Jews" in Fiume, where he was chief of police.
Fiume today is the Croatian city of Rijeka, on the Adriatic Sea.
Responding to the center's findings, the US Holocaust Memorial Museum in Washington has started taking down references to Palatucci in its summer show, "Some Were Neighbors: Collaboration and Complicity in the Holocaust."
It also took down a case study of Palatucci from its website.
In a June 7th letter to the museum, the Centro Primo Levi said Palatucci was never police chief in Fiume, where there were in fact barely 500 Jews - far fewer than the 5,000 previously stated - of whom 80 percent ended up in the Auschwitz concentration camp in Poland.
"Palatucci did not send hundreds of Jews to Campagna to be protected by his uncle," said the centre's director Natalia Indrimi, who wrote the letter to the museum.
"According to the database of foreign Jews interned in Italy, only 40 Jews were interned in Campagna (in southern Italy, where Palatucci's uncle was the influential Roman Catholic bishop) and not by the order of Palatucci," it said.
"Moreover it was a particularly vexed group - nine of them were eventually deported and one died following the hardship of internment."
The Centro Primo Levi also rejected the notion that Palatucci destroyed documents concerning Jews in Fiume to ensure that they were not sent to concentration camps.
"Palatucci never destroyed the records of the Jews, which have been in the past five years the main source of information for historians," Indrimi said.
"They are all available at the Rijeka state archive and any interested historian can consult them."
Overall, she said, Palatucci - whose name is honored in piazzas and promenades all over Italy - "continued to work under the Germans and to provide information on the few Jews who were still in the area."
"He was one of many government clerks who worked in the persecutory machine as if it were any other job," doing nothing to ease the persecution of Jews, she said. Indrimi called Palatucci "a willing executor" of fascist Italy's racial legislation who, "after taking the oath to Mussolini's social republic, collaborated with the Nazis."
So enduring is the Palatucci legend that a public space bearing his name was inaugurated in Polino, central Italy, just last weekend.
On the website of the International Raoul Wallenberg Foundation he is remembered as "an Italian hero in the Holocaust" who was arrested by the Gestapo, accused of conspiracy and sent off to Dachau.
In May 2005, the Anti-Defamation League in New York paid tribute to Palatucci as someone who did all he could to save Jews between 1940 and 1944 as Nazi German increasingly imposed its will on Benito Mussolini's regime.
"He issued false identity papers and visas, delivered food and money to those who were in hiding, gave warnings when the Nazis were planning a 'Jew hunt' and sent as many Jews as possible to the internment camps in Campagna and Puglia," it said at the time.