By Adam Easton
BBC News, Warsaw
Gen Jaruzelski remains a highly controversial figure in Poland
Poland's last communist leader, General Wojciech Jaruzelski, has gone on trial accused of committing a crime by imposing martial law in 1981.
Eight other former officials will also be tried for the clampdown against the opposition Solidarity movement, during which dozens of people were killed.
Gen Jaruzelski, who is now 85 and in poor health, says he had to act to prevent a Soviet invasion of Poland.
If found guilty he faces up to 10 years in prison.
Although there is little public clamour in Poland to send Mr Jaruzelski to prison, a crowd of journalists and members of the public packed the courtroom as the trial began.
Gen Jaruzelski and three of his co-defendants were identified before a panel of judges.
Four of the eight accused men were absent, citing poor health.
Reading the charges, the prosecutor said the men had violated their own communist constitution when they created what he called a "criminal military organisation" to implement martial law in December 1981.
The trial, in Warsaw, marks the first time Poland has held its former communist leaders criminally responsible for imposing martial law.
Immediately after the fall of communism in 1989, the new Solidarity government rejected calls for political retribution.
But in recent years moves to bring the senior communist party leaders to account for martial law have hastened.
Gen Jaruzelski has always maintained he chose the lesser evil when he ordered tanks onto the snowbound city streets on that night in 1981.
If he had not acted against Solidarity, he says, Soviet troops would have.
According to surveys, many Poles believe him.