Mr Berlusconi has reacted to the verdict saying he will not step down
Italy's highest court - the Constitutional Court - has overturned a law granting Prime Minister Silvio Berlusconi immunity from prosecution while in office.
Mr Berlusconi has reacted defiantly to the verdict saying he feels "invigorated" and has vowed to defend himself.
Here, readers in Italy react to the ruling and debate what next for their 73-year-old billionaire leader.
IN FAVOUR OF THE RULING
As an expat living in Italy this has all been incredibly entertaining but also incredibly tragic. It is true that Silvio is not the only politician here under investigation for corruption, many on the left are in the same boat. Italian politics has been in a mess for years, and with this they have dragged the media down the same drain. The Court's ruling brings a sense that there is still some sanity left.
Gavin Burns, Rome, Italy
I strongly believe that the Constitutional Court have done the ordinary job for which is in charge: to decide if a law is aligned to the Italian Constitution or not. Berlusconi's complains are no sense.
Luca Pizzasegola, Biella, Italy
Why doesn't he grow up and act his not-inconsiderable age? Berlusconi not only demeans his office, but also the Italian Nation he represents by his buffoonery and questionable dealings. How are we supposed to respect somebody who is indicted on multiple charges and then steamrollers through a law exempting himself from prosecution.
Even if he couldn't use his majority control of the media, questionable in itself, to get elected from among many ordinary Italians, all his actions to date scream out that he is not worthy of preferential treatment.
Jamie, Wendover, UK
I was always taught that people were to be considered innocent until proved guilty. The media seem to have judged him already without any proof. Neither fair nor correct.
Maggie, Milan, Italy
After the Constitutional Court's decision I felt I lived in a normal country for the very first time since Mr Berlusconi was elected. I've no idea what the implications will be, but Mr Berlusconi won't resign. Italians don't expect him to do so anyway. Shame shame shame!
The Constitutional Court's ruling suggests that one democratic principle - equality before the law - still holds in Italy. Many others have been fundamentally eroded under the Berlusconi government.
Barbara Graziosi, Trieste
I am very happy about the decision of the Constitutional Court. It's good to know that somebody still cares about human rights and the constitution in this country. Berlusconi has been playing a dirty game for ages. It's about time that he takes responsibility for his acts. Everybody is equal before the law.
Berlusconi has said that the court sides with the left. Hopefully some of his allies will work to get rid of him. Gianfranco Fini [of the right-wing National Alliance] for instance has already shown his dissent many times. Bear in mind, though, that Berlusconi is capable of anything. And when I say anything, I mean it.
Daniele Pimpa, Italy
My first reaction to the ruling was surprise. I could not believe that someone actually stood up to defend our constitution. Needless to say I am very pleased, although now that the court has called this law unconstitutional, I wonder what the president, Giorgio Napolitano, was thinking when he signed it. He is supposed to be the supreme guardian of our constitution.
He did not have to read it all, only up to Article 3, which states that all citizens are equal in front of the law. It would have been quite easy to spot the "dissonance". Anyhow, the foreign press need not to worry, Berlusconi will not resign. You will still have plenty to write about in the coming months. Keep up the good work, because we can't.
I'm glad that eventually the one man who claimed "while all Italians are equal before the law, the application of the law is not necessarily equal for all" has been proved wrong.
Nicola Gobbo, Treviso
All this should not have happened. Every Italian citizen has the opportunity to go and read our constitution, which declares that all citizens are equal in front of the law. For this reason, this appeal had no reason to be held. We had to call for the highest court to solve this "problem" because Italy itself cannot be called a "free country" any more. I am really glad the Constitutional Court did the right thing.
Alice Rizzo, Imola
For us this verdict represents a real form of justice, so we hope Silvio Berlusconi will resign like a prime minister should do in a real democracy.
Lorenzo Gasperoni, Cesena
I was positively surprised for once. But I don't think this sentence will cause Berlusconi's downfall unfortunately. At least the constitution is stronger than him, which is not something to be underestimated nowadays.
As an Italian citizen, I take the decision of the Constitutional Court as both a relief and a hope for the future. Still, I'm not sure Berlusconi will give up so easily. In 2004, a similar law was overturned by the court. What Berlusconi did was simply take his time. His lawyers are well capable of taking advantage of Italy's incredibly complicated prosecution system, so that he'll be able to get another immunity law put in place. Hopefully I am wrong, but I know the man pretty well.
It is a normal verdict of a normal country. But Berlusconi is not a normal PM.
It's one of the the greatest days for Italian democracy.
I am very, very happy. The court proved that Berlusconi's a citizen like all of us. Now he will finally face all the trials he was involved in. And possibly the truth.
The court had no option since the law is evidently against some paragraph of the Italian constitution. Mr Berlusconi needs two-thirds of both parliaments to change the constitution and pass the law. That's unlikely to happen. Now, what's next? He won't resign.
Giacomo Vaghi, Milan
This is an absolutely momentous decision. I believe nobody dared hope that the ruling of the Constitutional Court would be so categorical. Fortunately, the calibre of the judges has outweighed the opportunism of some members of the government. I have put a bottle of champagne in the fridge and I will be drinking it tonight.
Daniella Engel, Milan
Common sense tells us this can only be good news. I hope it precipitates a general change for the better in the politics of this country.
Some of us Italians hope that this can be the beginning of Berlusconi's fall. But we fear his followers could start an anti-democratic reaction. Every place in Rome near the Premier's palace is closed to the public.
Michaela Barilari, Florence
OPPOSED TO THE RULING
The Constitutional Court had no choice, because there's a specific article that establishes the equality of each man in Italy, article violated by the "Lodo Alfano". But, in some way, everything is ruled by Mr. Berlusconi here, so all Italy was afraid of a legitimistion of his immunity.
We need help. A lot of help. An external help. UE must help us to find a way to restore freedom in Italy, starting from media. There's an HORRIBLE distortion of reality in this country.
Marco Nobile, Milan
I do not trust the justice system in Italy. Most judges are not impartial. They have radical political views, and are using their powers to undermine a legitimate government that they oppose. Furthermore there is a lot of money in play here, 750 Million Euros that Berlusconi must pay to De Benedetti, who by the way is behind several Italian newspapers campaigning against Berlusconi, backed by the opposition left. Italians like me have had enough of these political games and do not care what a left-controlled newspaper says because we can make our minds up from the facts.
Giorgio Chinotti, Milan
I believe that the Constitutional Court is just trying to kick Mr Berlusconi out. He is not the only politician facing corruption charges. The left wing ones could be worse than him. Instead of ruling the country and talking about serious matters, the media here only talks about this garbage.
You can't understand Italy and its politics if you are not Italian. Even if you have been living here for ages, you can't! Berlusconi belongs to our DNA because Italians love freedom and democracy, the opposite of what the left-wing proposes. The left, which is made up of a wide range of notorious politicians and magistrates, is united only by one goal: to destroy him and nothing else, that is their political plan. We have to remember, as a lot of people and the international press usually forget it, that Berlusconi hasn't been sentenced in any trials yet.
Roberta Negriolli, Parma, Italy
Personally I don't care about this story. Berlusconi is the best prime minister we have had in 150 years. Surely a self-made man must have done something wrong during his career but if all the people respect all the laws everything goes wrong.
I don't think it's any secret that a sector of the Italian judiciary has a political agenda. That doesn't mean Berlusconi's necessarily innocent, of course, but it does mean that certain left-wing judges would like nothing more than to embarrass him (and, in passing, the country) by dragging him through the courts while he's in office. In a country with an independent judiciary, there would be no reason to grant such immunity. Here, it may be the only way to ensure government on an even playing field. Berlusconi will be fair game when he's voted out in any case, so why not let him get on with his job for the moment? Or are the left worried that this may in fact be the only way they are capable of getting him out!
Simon Tanner, Messina
It's a political sentence. The bench in Italy hates Berlusconi. However, Silvio is strong and his government won't fall.
Andrea, Lecce, Italy
It's the last act of one of the most brutal annihilations of a leader ever seen before. The pact of war between major powers aimed at wiping out Berlusconi despite his popular support is being completed and I believe that this time, Berlusconi will not survive.
Paolo Mici, Italy
Berlusconi maybe 'furbo' (cunning) but he is a popular man as well as being a self-made man. His popularity will remain regardless. This is just one aspect of Italian politics that other countries don't understand. The judiciary is left, just like the old Roman system. This will remain until the last remaining communists stand down.
For years Berlusconi has been continuously hounded by what I can only describe as a carnivorous left wing intent on ousting him. I realise that it's not politically correct to support Berlusconi and from the UK his position may seem untenable, however I believe he's the best prime minister Italy could have at the moment. His demise would unfortunately be a political coup d'état.
Gail Jones, Milan