But after Italy's persistent corruption scandals, the title Onorevole has become a sick joke. Many a bearer who used to strut and preen now walks in fear of the shouts of 'thief' hurled by members of the public when they realise who he (mostly) or she is.
Returning home at the end of the week on the Rome-Milan Settebello express, the Onorevoli used to stand around talking loudly so that other passengers could see what Important People they were. Now, travellers say, they cower in corners, hoping no one will spot their MP's rail pass when the ticket controller comes round.
But their insecurity goes even deeper. Many MPs, faced with the collapse of their public image, have developed deep neuroses, according to Piero Rocchini, former resident psychiatrist to the Chamber of Deputies, who has treated several of them.
In a book, Le Nevrosi del Potere (The Neuroses of Power), published recently, he claims Italy's democracy has produced MPs who are psychologically incapable of coping with the reforms needed to improve the system.
Very few seek election to pursue political ideals or defend their fellow-citizens, he writes. 'Politics is seen simply as a means to gain personal advantages', either in tangible benefits or in prestige. And as Italy's political system since the Second World War has given MPs power and status with extremely little personal responsibility, it has attracted many people who would be failures anywhere else.
'If I leave politics what will I do?' one MP asked Dr Rocchini. 'It would be complete emptiness. I would have to push and shove with people in the Post Office whereas now I only have to raise a finger and I have everything.'
For the Italian MP the most important thing in his life is not the voters or his constituency but his party. The party is power: it gives him his constituency, prestigious jobs, a cosy haven of allies, it makes his decisions for him, and gives him his identity. The party, Dr Rocchini says, becomes his mother figure.
But thanks to a change in the electoral law, which allows voters to pick from among a number of candidates on a party slate, the party has become a jungle where members now have to compete with each other as well as with other parties for the voters' favour. In the run-up to the elections in April last year, when the legislation was applied for the first time, the number of his patients increased by 40 per cent.
Some MPs reacted with a no- holds-barred attitude, others with depressions, phobias, anxiety crises. 'It was as if they passed from a mother's womb, where all is cushioned and safe from danger . . . to a turbulent outside world so vast that it is unbearable for someone who, deep inside, feels too small.'
Meanwhile, many MPs are suffering from what is termed the 'Di Pietro syndrome', after the magistrate who is leading the biggest corruption investigations. Even though many are doubtless innocent, the investigations have led to the general discrediting of the whole political class.
As thanks for his insights, Dr Rocchini was fired because they 'did not conform to his professional ethics'. Dr Rocchini insists that not one of his patients could be identified and he has no regrets. It is his duty as a doctor and a citizen, he says, to find ways to ensure that the voters get better representatives in future.