Scientists say the sentencing of six Italian seismologists for underestimating the risk of a 2009 earthquake was a blow to scientific freedom, and some likened it to the persecution of Galileo.
From research into new drugs to identifying rogue asteroids that could strike Earth or even weather forecasting, all branches of science that advise the public about risk are at threat, they said.
Lord Robert May, an Oxford University professor of zoology and former head of Britain's Royal Society, one of the world's most prestigious academies of science, said 'the sentence is truly shocking.
'The verdict might have been understandable in the Dark Ages, standing alongside the persecution of Galileo, but in today's world it simply is an embarrassment to the Italian government and anyone associated with it,' he said.
Michael Halpern of US-based group the Union of Concerned Scientists (UCS) observed that the verdict came 'from the home country of Galileo. I guess some things never change.'
Without the right to speak freely and independently, scientists become scapegoats, he said in a blog.
'Scientists need to be able to share what they know - and admit what they do not know - without the fear of being held criminally responsible should their predictions not hold up,' he said.
Galileo is viewed as a martyr of science. Threatened with torture by the Inquisition, the astronomer was forced in 1633 to recant his assertion that the Earth moved around the Sun, and not the other way around as the Catholic Church then maintained.
'The verdict is perverse and the sentence ludicrous,' the journal Nature said in an editorial.
'Already some scientists have responded with warnings about the chilling effect on their ability to serve in public risk assessments.'
It added: 'All efforts should be channelled into protest, both at the severity of the sentence and at scientists being criminalised for the way their opinions were communicated.'
Alain Carpentier, president of France's Academy of Sciences, said the ruling was 'a very dangerous precedent'.
'Scientists make their judgement on the basis of knowledge at that given moment. They cannot be reproached for the fact that knowledge is limited, if they have mobilised all the knowledge available,' he said in an email to AFP.
The six seismologists and a government official were sentenced to six years in jail in the central Italian city of L'Aquila for multiple manslaughter on Monday, and ordered to pay more than nine million euros ($A11.39 million) in damages.
The sentence was higher than that demanded by the prosecutor.
The defendants were members of the country's risk assessment committee, which met in L'Aquila on March 31, 2009, less than a week before a 6.3-magnitude quake killed 309 people, destroying homes and ancient churches and leaving thousands homeless.
Ahead of the trial, 5000 scientists, including some of the world's leading academies, published an open letter to condemn the indictments and point out it was impossible to predict when an earthquake would take place.
Under the Italian justice system, the seven remain free until they have exhausted two chances to appeal the verdict.
Bill McGuire, a professor of geophysical and climate hazards at University College London, described the verdict as 'extremely alarming'.
'If this sets a precedent, then national governments will find it impossible to persuade any scientist to sit on a natural hazard risk evaluation panel,' he said in quotes reported by Britain's Science Media Centre.
'In the longer term, then, this decision will cost lives, not save them.'
In an apparent echo of this warning, top Italian physicist Luciano Maiami on Tuesday announced he was quitting as head of the risks committee.
'It is impossible to produce serious, professional and disinterested advice under this mad judicial and media pressure,' he said.