The man whose fireworks display set off a 2003 blaze that killed 100 concertgoers is sitting in prison, but for many victims' relatives, the first of the two most important trials in the case is only now about to begin.

Jury selection begins Tuesday for Michael Derderian, who with his brother owned The Station, the one-story, wooden nightclub that quickly became a deathtrap when stage pyrotechnics ignited the soundproofing foam that covered its walls and ceiling.

Still fiercely angry more than three and a half years after the fire, victims' relatives see the Derderians as penny-pinchers who created unsafe conditions in the club and have never shown the same remorse as the man whose pyrotechnics started the fire.

Daniel Biechele, now serving four years in prison, was tour manager for the band Great White, which was on stage when the fire started and lost guitarist Ty Longley. Biechele pleaded guilty and tearfully apologized in court in May.

James Gahan, whose 21-year-old son, Jimmy, died in the fire, said he talked with state Attorney General Patrick Lynch at Biechele's sentencing. "He just asked me what I thought, and I said, `Now, the real work starts.'"

Michael Derderian's trial is expected to last months and Jeffrey Derderian's trial will follow. Both face 200 counts of involuntary manslaughter — two counts for each person killed under separate legal theories. Each count carries a maximum 30-year sentence.

More than 200 people were injured in the blaze. Many people who live in Rhode Island, the nation's smallest state, know someone who was killed or injured, or one of their relatives.

"The Derderians feel like the targets that the public has focused its angst, its anger on," said Andrew Horwitz, a professor at the Roger Williams University law school in Bristol.

Prosecutors say the Derderians showed a pattern of poor management and dangerous decisions, including installing the highly flammable polyurethane foam in violation of the state fire code and allowing bands to use pyrotechnics as part of their acts.

They also say the Derderians did several things that made it harder to evacuate the club: packing too many people into the building, having an exit door that swung the wrong way and failing to have illuminated exit signs.

The Derderians say the band never had permission for the pyrotechnics, but band members contend they did.

The brothers' lawyers say they were never told the foam violated the fire code, and say reports by fire inspectors who surveyed the club make no mention of the material.

Those arguments fail to satisfy people such as Chris Fontaine, who lost her 22-year-old son, Mark.

"Anybody who owns that type of an establishment bears a responsibility to know what the codes are and to follow them accordingly," said Fontaine, who plans to attend every day of the trial. "These are people who put lives at stake."

"It was their building," said Claire Bruyere, whose daughter, Bonnie Hamelin, 27, was among those killed. "They were supposed to make everyone OK."

The attorney for the Derderians, Kathleen Hagerty, said the families' anger is "certainly understandable."

"We're looking at the case, obviously, legally, which is very different," Hagerty said. "If anything, I think this case will certainly shine a bright light on all that went wrong in this tragedy."

At a news conference two nights after the blaze, Jeffrey Derderian broke down several times as he expressed his grief over the fire.

The brothers attended funerals of some victims and have made voluntary payments to the families of employees killed in the fire. They also declared bankruptcy, however, freeing them from liability in pending lawsuits filed against them by victims' families and survivors.

Paul Vanner, The Station's stage manager, said the Derderians were rookie club owners but followed the rules. "There's no way that they would have known" the foam was dangerous, he said.

The salesman who sold the Derderians the foam sent a letter to prosecutors saying his company's policy was to not educate customers about the potential dangers of the foam, but the company's general manager has said that claim was not true.