The verdict was a shock for many who assumed that the influence of the Salinas family would ensure acquittal.
Commentators suggested the judge, in a country where the judiciary has traditional ties to the ruling Institutional Revolutionary Party (PRI), may have imposed the maximum sentence as a signal to the pontiff and the world that this country was moving from the impunity long enjoyed by PRI leaders, including the Salinas brothers.
Prosecutors said a family dispute and an argument over political pay- offs precipitated the 1994 murder of Francisco Ruiz Massieu, a former Salinas brother-in-law.
At the time, Raul Salinas, now 52, ran the country's food distribution agency, where he is thought to have amassed hundreds of millions of dollars by siphoning off state funds.
Judge Ricardo Ojeda admitted there was no proof that Raul Salinas had ordered the shooting of Massieu, 48-year-old No 2 of the PRI.
"There was no confession, nor direct proof," he said in a written verdict. "The defendant's responsibility for the crime was shown through circumstantial evidence."
Although most Mexicans despise the Salinas brothers - Carlos left the country soon after his brother's arrest in 1995 and lives in exile in Ireland - most agreed that there was little evidence linking Raul to the murder. Salinas's lawyers said they would appeal and had two more chances by law to free their client, who has come to symbolise how the once untouchable power of Mexican politicians has been undone by democratic change.
"There was not a single shred of evidence that merited this sentence," said Juan Velazquez, the defending attorney.
The fact that Carlos Salinas, while still president, appointed Mr Ruiz Massieu's brother Mario as special prosecutor for the case further confounded public opinion.
Mario Ruiz Massieu, accused of trying to cover Raul Salinas's alleged role, suddenly fled the country. He is under house arrest in the United States on currency-smuggling charges. A second prosecutor, Pedro Chapa Bezanilla, quit after he was accused of trying too hard for Mr Salinas's conviction.
He fled the country after allegedly conspiring to frame Mr Salinas by planting a corpse on his ranch. The body was supposed to be a missing congressman involved in the conspiracy to murder Mr Ruiz Massieu. But it was an unrelated disinterred cadaver.
Raul Salinas's lawyers condemned yesterday's verdict as political.The conviction was an important victory for President Ernesto Zedillo, who risked his reputation in approving the arrest and broke unwritten political rules that protected former presidents and their families.
His party, the PRI, called the decision a triumph for the legal system. "We hope that the judge and judicial branch act strictly in accordance with the truth and the law," said Carlos Rojas, second in command at the PRI, and social development minister under Salinas.
Pope John Paul II arrived in Mexico yesterday for a visit which will be more akin to a sports event, with 25 official sponsors, from Pepsi to a crisp company, using his image on their products. It was rumoured that his robes might even carry a Sabritas crisps logo.
A Vatican spokesman said sponsorship was needed to cover the visit's $2m (pounds 1.25m) costs. But he said the Pope would not wear or pose next to any commercial logo. "The Papa will not come out dressed as a papa," he said, playing on the fact that "papa" means both "pope" and "potato" in Spanish.
The ailing 78-year-old pontiff, on his fourth visit to Mexico in 20 years, will sign a document outlining church strategy in the Americas for the next millennium, including how to staunch the spread of Protestantism. About 90 per cent of Mexicans list themselves as Catholics, but that may often be to avoid discrimination.Reuse content