Letta slams Grillo remarks on TV host
What's it like to be married to a murderer's son? asked M5S head03 February, 14:00
Bignardi's husband Luca Sofri is the son of leftist ex-militant Adriano Sofri, convicted for ordering the murder of police commissioner Luigi Calabresi in a case that inspired Nobel prize winner Dario Fo's best-known play.
Calabresi, who was vilified by Sofri's leftist journal, was eventually found to have had no role in the death of anarchist Giuseppe 'Pino' Pinelli who fell from a Milan police station window in 1972.
After serving his sentence for the crime, Sofri continued his career as an intellectual, writer and journalist, with son Luca following in his footsteps.
Letta said about the M5S leader's broadside: "It's scandalous, I cannot refrain from commenting on Grillo's crazy remarks against Daria Bignardi and her husband". The premier said that, faced with the "race towards barbarity taken by Grillo, apparently without end, there can be no tolerance towards this kind of politics".
The M5S has been filibustering legislation in parliament and sparked a scuffle last week in which a centrist MP slapped one of its members.
It is trying to impeach Napolitano for allegedly not playing his Constitutional role as impartial arbiter.
Daria Bignardi conducted an interview Friday with M5S MP Alessandro Di Battista and asked him about having an ex-Fascist father.
On his blog Monday, Grillo said "how does your son feel in school about having a grandfather who ordered a murder? What's it like to have married the son of a murderer".
The firebrand former comic also criticised Bignardi for an interview with journalist and writer Corrado Augias who described the M5S as "neo-Fascist" - prompting one M5S member to publicly burn a copy of Augias's latest book at the weekend. Adriano Sofri was freed in January 2012 after serving a jail term for ordering the murder of Calabresi.
Sofri, 71, had been under house arrest for health reasons since 2007 and had been permitted furloughs.
In 1990 he was given a 22-year sentence for Calabresi's murder.
In November 2005 he almost died after suffering a ruptured oesophagus and his sentence was subsequently suspended as he convalesced.
Parole judges ruled he could serve out the rest of his sentence at his home in the small town of Impruneta near Florence.
The ex-leader of Lotta Continua, a hard-left political movement active during the 1970s, was found guilty of the Calabresi murder along with two former fellow militants, Ovidio Bompressi and Giorgio Pietrostefani.
The trials, appeals and various retrials of the three, who were first arrested in 1988, marked one of the most complicated and drawn-out cases in Italian legal history.
The convictions were definitively upheld in 2000.
Bompressi was granted a presidential pardon for health reasons in May 2006.
Pietrostefani had fled to France to avoid jail.
Sofri, who has always maintained his innocence, has become a columnist, mostly for the left-leaning daily La Repubblica, and a pacifist intellectual who regularly contributes to the country's political debate.
Commissioner Calabresi was gunned down in front of his Milan home on May 7, 1972.
He had become a figure of loathing in hard-left circles after anarchist Pinelli fell to his death in suspicious circumstances from a window at Milan's police headquarters in 1969.
The case was the subject of Nobel prize-winning playwright and leftist militant Fo's best-known work, Accidental Death of an Anarchist.
In 1971, Calabresi was put under investigation for Pinelli's murder but charges were dropped because of lack of evidence.
Sofri's supporters long lobbied for a presidential pardon for the former militant.
But Sofri's case was more complicated than that of Bompressi because he has always made a point of never asking for a pardon himself, saying that this would be an admission of guilt.