Just over a year ago, the central Warsaw courthouse on Swierczewskiego Street was the scene of wild jubilation when Solidarity supporters formally registered their union as a legal institution in Poland. Today, as the same building is being used for the first trials of the organizers of resistance to the new military authorities, the atmosphere has turned to sullen anger and despair.

The three alleged ringleaders of a two-day occupation strike at the F.S.O. car factory in Warsaw were led into court in handcuffs. Janusz Pienkowski, 42, was still wearing blue overalls. As wives and relatives burst into tears, he grinned cheerfully and waved his fingers in a defiant victory sign.

Pienkowski was followed by Zygmunt Kaminski, 58, a quality-control technician, and Edward Glowacki, 37, the plant's delegate to Warsaw regional Solidarity headquarters.

Under martial law, the maximum penalty for disobeying orders in militarized industries--such as mines and ports--is death. Civilian courts can sentence organizers of strikes to up to five years' imprisonment in summary proceedings without the right of appeal.

So far, sentences have averaged around three years. Legal arguments are cut to a minimum but, unlike political trials in most other Communist countries, outsiders have been allowed into the courtroom in addition to family members.

The trial of Pienkowski, Kaminski and Glowacki--all experienced workers with many years' service at F.S.O.--appeared typical of the way in which the authorities intend to deal with suspected troublemakers. Officials have said that, in addition to those interned, nearly 800 people have been arrested for breaking martial law regulations.

The defendants had all been arrested after riot police, supported by tanks and water cannon, stormed the F.S.O. factory on the outskirts of the capital. Most of the strikers--who had been staging a last, desperate protest against the imposition of martial law in Poland on Dec. 13-- were allowed to go home. But the new military commissar at the factory, a colonel, pointed out Pienkowski, Kaminski, and Glowacki, as the organizers, and they were taken off to prison.

As their families searched for them throughout Warsaw, the three alleged strike leaders underwent their first interrogation at the Bialoleka Prison on the outskirts of town where many detainees are held. It was not until they appeared in court, after Christmas, that they were allowed to consult with their defense lawyers.

The indictment was read out in a dull, hurried voice by the woman prosecutor, a blonde in her mid-30s who sat at the same long wooden table as the judge and his two assessors. Above the judge hung a picture of an eagle, Poland's national symbol, which used to be displayed prominently at every Solidarity meeting around the country. Outside the somber courtroom, snow-covered trees glistened in the sunlight.

" . . . the three accused, on the days of Dec. 14 and 15, 1981, despite the fact that the activities of the Solidarity trade union had been suspended by martial law, took part in a strike, were elected as members of a strike committee, and directed the protest . . . "

The indictment said the defendants had demanded the release of imprisoned Solidarity activists and the lifting of a ban on trade unions and other social organizations. They had failed to listen to the appeals of the military commissars at the plant and had set up worker guards.

But the prosecutor, wearing a black robe trimmed with red, conceded that "none of the three accused has a criminal record. Opinions about them from their neighbors are good."

It quickly became clear that the main line of defense was that the three men should not be considered strike leaders. The protests began spontaneously out of a mood of intense anger at the plant against the imposition of martial law. It was unfair to single out three workers. Either all 2,000 or so strikers should be sent to prison, or none at all.

The defense lawyers later explained privately that this was the only possible line they could take. Under Polish law, they had no right to question the legality of the martial law regulations themselves, which were rushed through a nighttime meeting of the state council and never ratified by parliament.

Protests by the defense lawyers at the summary nature of the trial were overruled by the judge after a brief adjournment. Fidgeting nervously with a pencil, the judge also ordered Glowacki's 15-year-old son Darek to leave the courtroom, saying he was too young to attend a trial.

Darek waited outside in the corridor. A small, slight boy with blonde hair falling over his eyes, he recalled how the police had originally come for his father shortly after midnight on Sunday, Dec. 13, several hours before the declaration of martial law. Both his parents were out at the time and he and a friend of his had been sleeping alone in the house.

"There was a sudden banging at the door. They said they were the police but I didn't want to open it. So they smashed the door down with axes and forced their way in. I was very frightened."

Darek described how the police had searched the apartment for his father and ripped open bundles of old newspapers he had been collecting to sell as scrap. They were apparently looking for Solidarity leaflets but didn't find anything. At one point, one of the uniformed policemen pointed to Darek's white poodle and asked sarcastically why it was so well fed at a time when it was very difficult for ordinary Poles to buy meat.

Since he was away from home, Glowacki escaped arrest that first night and was able to make his way to F.S.O. The police caught up with him two days later--naked and dripping wet while taking a shower.

Inside the courtroom, the first defendant to give evidence was Pienkowski. He explained that the strike had started after the manager of the plant had called a mass rally to warn the workers of the penalties for disobeying martial law regulations. It was the rally that led to the strike--so, really, the managing director should take the blame for what happened.

Speaking in a loud, rasping voice, Pienkowski said it was not just Solidarity members who had taken part in the strike. They had been joined by members of the official trade unions, including some Communist Party members as well. The workers felt confused, nervous, disoriented. It was impossible to prevent a protest.

Pienkowski insisted that at no point was a formal strike committee set up. He had agreed to help protect the machinery against possible sabotage but this did not mean that he was a strike leader. He admitted holding a discussion with the colonels during an early stage of the strike.

"They told me that if we went back to work now, they would forget the whole business and not even mention it in their reports. I asked them if that meant a return to the lies and deceptions of the past."

That first evening, Pienkowski said he was almost lynched by the workers when he suggested that the strike be limited to 24 hours. Everyone voted for an open-ended occupation. The workers were so incensed that the director had to get bodyguards.

When it became clear that the factory was about to be stormed by riot police, Pienkowski told all the workers to keep together and stay calm so there would be no incidents. The police commander tried to address the crowd through a bullhorn but no one could hear so Pienkowski lent him a microphone.

"The commander shouted: 'Aha, you're the leader. Seize him. Take him away.' "

Questioned by the prosecutor about his present attitude to martial law, Pienkowski replied that--since the strike--he had spent all his time in prison so lacked sufficient information to make a proper judgment. The situation, however, was obviously complicated. "It is so complex that it is difficult to describe it in words. I can't understand why, if all the Solidrity extremists are behind bars along with the antisocialist forces, tanks have to be out on the streets all the time," he said.

The next to give evidence was Kaminski, who said he had joined Solidarity "right at the beginning" after becoming disillusioned with the old metalworkers' union. When he came to work on the Monday after martial law, he found that his colleagues were angry and resentful. Once the strike had been declared, there was a need to appoint guards and, as an employe of 27 years standing, he felt a responsibility to the plant.

He recalled a conversation with the police commander at the scene who justified martial law by saying: "Your Solidarity leaders wanted to prepare a bloodbath for us."

"That's not true," Kaminski said he replied. "We wanted to unite the nation, nothing else."

After the police threatened to use force to break up the strike, he asked them: "How is it possible for Polish soldiers to aim weapons at Polish workers? What sort of morality is that? What will history look like? Strikes are a result, not a cause of unrest. Help us tackle the cause."

On the second day of the strike, Tuesday, Dec. 15, Kaminski said the workers became very worried. "Some people were crying, saying it was terrible that such a beautiful idea as Solidarity had been broken. But some good, wonderful people still brought us food."

The strike ended at 10:15 that night. Resistance was not even contemplated from the beginning because "this was the philosophy of our union. I myself believed that no one should be hurt because of me, no one should lose his life on my account"

During Kaminski's testimony, the prosecutor seemed bored. She spent most of the time looking down at her knees or biting her nails. Occasionally she asked questions, but with little enthusiasm--as if everything already had been decided and there was little point arguing the case.

A key legal point was whether the defendants had signed a communique outlining the demands of the strikers. They agreed they had but only at the insistence of the plant's director who said that otherwise he could not accept the documents.

Glowacki, an intelligent-looking man with glasses, testified that the alleged committee had only been set up after the strike had already started. It could not, therefore, be accused of instigating the protest. The defendants were not empowered to negotiate on behalf of the workers.

After a break, the court began hearing the evidence of witnesses for the prosecution. They chose their words carefully and most tried to give an impression of sympathy for the accused.

The plant director, Witold Dabrowski, said that, despite the strike, the management had been allowed to work undisturbed. He himself had no one to negotiate with "as there was no strike committee." In his opinion, the strike had been caused by the mass arrests of Solidarity activists.

A Communist Party secretary at the plant, Jan Kobielarz, also did his best to support the contention of the defendants that they had not led the strike. He said he did not recognize any of the accused as having spoken at rallies during the occupation of the factory. The judge pointed out to him that, during preliminary investigations, he had named Zygmunt Kaminski as the main speaker.

"Well, the name was something like that, Kowalski or Kaminski, but not Zygmunt Kaminski."

After more pleas by the defense to transform the trial from a summary martial law case to regular proceedings (overruled), the judge ordered an adjournment until Tuesday.

Outside the courtroom, a dozen or so F.S.O. workers who had attended the trial expressed their anger at the proceedings. "What the hell are these people on trial for?" They're good workers, just like us--not criminals." At that point, the defendants were led down to the cells, once again in handcuffs. Kaminski made another V-sign to a ripple of applause.

A sympathizer, who had observed trials of workers in July 1976 following food riots remarked on the difference between the two occasions. Five years ago, the authorities had picked on semi-criminals in order to make the case against them look as convincing as possible. This time, the accused were much more obviously solid citizens on trial for their opposition to the Communist regime in Poland.

"In 1976, most of the speeches were made by brave defense lawyers. There were wonderful flights of rhetoric about freedom and democracy, the kind of thing we hadn't heard in Poland since the Communists came to power after World War II. This time, all that seemed obvious and didn't need to be said. The accused were able to defend themselves," he explained.

"Perhaps, after all, we have made some progress."