Maurizio Degl'innocenti / EPA, file

More than 300 people died after a quake in L'Aquila, Italy on April 6, 2009. The city was strewn with rubble and thousands left homeless.

A court in the Italian city of L’Aquila on Monday convicted six scientists and one government official of manslaughter for failing to give sufficient warning of a fatal earthquake that hit in 2009.

The judge sentenced each man to six years in jail and ordered them to pay compensation and legal fees.

The prosecution case had centered on a meeting the seven defendants, members of a commission on natural disasters, held in L’Aquila on March 31 2009, in which they told residents there was no cause for concern after a series of minor shocks had rocked the city in the preceding six months.

Less than a week later, in the early hours of April 6, a 6.3-magnitude quake reduced much of the medieval city to rubble, leaving 309 people dead and more than 60,000 homeless, according to news reports at the time.

In a  memo issued after the March 31 meeting, the experts concluded that it was "improbable" that there would be a major quake, although they stopped short of entirely excluding the possibility.

The public prosecutor, Fabio Picuti, had accused the defendants of giving "inexact, incomplete and contradictory information" about whether the smaller tremors should have constituted grounds for an official quake warning.

Picuti acknowledged that predicting where, when and with what force a quake would strike is scientifically impossible, but said the risk of a big temblor was not taken seriously enough. He argued the commission’s discussions were too generic and completely failed to address the risk at hand.

“The key word in this trial is the word analysis. How do you proceed with an analysis of risk, or an analysis of seismic risk? Do you proceed in a manner that the defendants have shown us?” Picuti said in comments to the court on Monday. 

Defense lawyer Franco Coppi told the court it would indeed be a problem if the risk had been foreseen and inevitable.

“But if an event cannot be foreseen, and more importantly if it is unavoidable,” Coppi said. “It is impossible to speak about how a risk has not been foreseen."

Italy's long earthquake history hidden in ancient records

The decision to prosecute the seven, who are among leading figures in Italian seismology, had caused alarm among the scientific community.

In a report commissioned by the Italian government in the immediate aftermath of the L’Aquila disaster, the International Commission of Earthquake Forecasting for Civil Protection (ICEF) highlighted the many difficulties of making accurate time-sensitive predictions, within timescales usually calculated in decades, not weeks or months. 

But the ICEF report’s findings also called for better public communication, not just of day-to-day temblor hazards but also by setting alert levels that take into account the advantage of being psychologically prepared for when a quake hits.

Scientists on trial for failing to predict Italian quake

An open letter to Italian president Giorgio Napolitano, signed by more than 5,000 members of the international scientific community, criticized the proceedings.

In a separate letter to the Italian president, the American Association for the Advancement of Science called the charges "unfair and naïve," saying, "There is no accepted scientific method for earthquake prediction that can be reliably used to warn citizens of an impending disaster."

Despite the protests, the trial opened in September 2011.

The seven convicted of manslaughter were:

Enzo Boschi, then-president of Italy's National Institute of Geophysics and Volcanology (INGV) in Rome;

Franco Barberi, at the University of 'Rome Tre';

Mauro Dolce, head of the seismic-risk office at the national Department of Civil Protection in Rome;

Claudio Eva, from the University of Genova;

Giulio Selvaggi, director of the INGV’s National Earthquake Centre in Rome;

Gian Michele Calvi, president of the European Centre for Training and Research in Earthquake Engineering in Pavia;

and a government official, Bernardo De Bernardinis, then vice director of the Department of Civil Protection.

The Associated Press contributed to this report.

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