ROME (Reuters) - Italy’s parliament on Wednesday approved a long-awaited law criminalizing torture, but critics said it had been so heavily watered down that many abuses may still go unpunished.

Italy ratified the 1984 United Nations Convention against Torture in 1988 but until Wednesday had never legislated to make it a criminal offence.

More than four years after the bill was presented, the Chamber of Deputies finally passed it by 198 votes to 35 but most of the members of the 630 seat lower house were either absent of abstained.

The bill, which says torture can by punished by up to 12 years in prison, was backed by the ruling Democratic Party (PD) and opposed by the center-right opposition which said it would make it harder for the police and military to do their job.

“Almost 30 years after ratifying the U.N. Convention, we have filled a huge vacuum in our legal system that was repeatedly condemned by European and international bodies,” said the PD’s Donatella Ferranti, head of the chamber’s justice committee.

Left-wing parties and the anti-establishment 5-Star Movement abstained, saying the bill had been so heavily amended in parliament that it was now of little use.

The senator who originally presented the bill in 2013 abstained for the same reason when it was approved in the upper house two months ago.

Critics say the law’s definition of torture is too narrow, requiring for example that violent conduct must be repeated and continuous and cause a “verifiable psychological trauma,” meaning many acts of cruelty may fall outside it.

When the bill was approved in the Senate in May, Amnesty International called it “unpresentable” and “incompatible with the U.N. Convention against Torture.”

In its final version it had been designed to protect Italian military and police “at all costs,” the rights group said.