UPDATE 1-Critics say justice reform made to save Berlusconi

* Berlusconi allies say law will benefit all Italians

* Proposal would extinguish two Berlusconi trials

* Opposition vows strong fight; says law unconstitutional

(Adds ex-partner calling law "pile of rubbish", paragraph 7)

By Philip Pullella

ROME, Nov 13 (Reuters) - Prime Minister Silvio Berlusconi says his government's justice reform plan will benefit all Italians but critics say it is just the latest in a string of tailor-made laws to help him avoid corruption trials.

The draft law, which was presented by Berlusconi allies in the Senate on Thursday, calls for one of the most radical reforms of Italy's snail-paced justice system since the end of World War Two.

It would impose a total six-year limit on the three stages of court cases -- initial trial, first appeal and final appeal -- in a country where trials can last more than a decade.

"This is not a tailor-made law. It is a law that affects everyone," said Gaetano Pecorella, a parliamentarian of the governing centre-right People of Freedom bloc who is also one of Berlusconi's lawyers.

But the opposition, magistrates and consumer advocacy groups say it is yet another "ad personam" law, using the Latin term meaning "for a person".

"What it all boils down to is impunity for Berlusconi," the left-leaning La Repubblica newspaper said in an editorial.

Pierferdinando Casini, leader of the centrist Union of Christian Democrats who was a partner with Berlusconi in a previous government and who Berlusconi has been trying to woo back to his side, dismissed the law as "a pile of rubbish".

If the law is passed in its current form, which commentators say is likely because the centre right has a comfortable majority in both houses of parliament, two of Berlusconi's current trials will be declared extinct.

One is a trial against him on charges of false accounting in the acquisition of TV rights by his Mediaset television empire.

Another is a case in which he is accused of bribing British lawyer David Mills to give false testimony in 1997 to protect Berlusconi's business interests.