The Ghost Ship criminal trial officially begins Tuesday, more than two years after 36 people died in a blaze at an unsanctioned artists warehouse that authorities called a firetrap.

Here’s what to expect from the proceedings, which will be held at the René C. Davidson Courthouse in Oakland.

The defendants

Derick Almena and Max Harris ran the day-to-day operations at the artists’ collective known as the Ghost Ship at 1315 31st Ave. in Oakland’s Fruitvale district.

Almena, 48, was the master tenant who leased the building from owner Chor Ng and her family, and converted it into a live-work artists collective, without proper permits. His lawyer is defense attorney Tony Serra.

Harris, 29, lived in the warehouse as the Ghost Ship’s creative director, and helped plan a music event on the night of the fire that drew dozens of partygoers to the second floor. Harris is represented by defense attorney Curtis Briggs.

Almena and Harris each face 36 charges of involuntary manslaughter. If convicted on all counts, each could get up to 39 years in state prison.

The prosecution

Alameda County Deputy District Attorney Autrey James took on the role of lead prosecutor in the case after co-counsel David Lim announced last month that he would leave to start his own firm.

What happened the night of the fire?

The evening of Dec. 2, 2016, a massive blaze tore through the Ghost Ship warehouse, where about 100 people had gathered for an electronic music party.

People escaped from the burning building and gathered outside, but none of them “seemed overly excited or distraught,” according to an investigative report. First responders and survivors appeared to be unaware that there were people trapped inside the burning building. Firefighters called into the building “for a response from people possibly inside but got no answer.”

The Ghost Ship, firefighters later said, was a labyrinth of passageways crammed with flammable materials. A stack of wooden pallets served as the only unblocked “stairway” to and from the second floor, where the party was being held. There were no fire exits.

Seven victims were later recovered from the second floor, in a section that didn’t collapse or burn but showed extensive smoke damage. The other 29 were found either in the rubble from a partial collapse of the second floor or on the ground floor. All 36 died of smoke inhalation.

Why are Almena and Harris criminally charged?

Prosecutors say Almena and Harris are criminally responsible for creating the tinderbox and packing it with dozens of guests on the night of the fire.

Prosecutors say Almena breached the terms of his lease by illegally allowing 15 to 25 people to live in the building, and that he scoffed at suggestions to make it safer. The building was not outfitted with sprinklers or an automatic fire detection system, and the party’s organizers didn’t have a permit from the city to hold a concert at the warehouse.

What are the defendants expected to argue?

The defense teams have largely sought to redirect blame onto the building’s owner and the city, who they say should have better policed the space. They say city officials had been in the building on several occasions prior to the fire, and failed to flag potential dangers.

Why has it taken more than two years to go to trial?

A trial initially scheduled for July 2018 was called off at the eleventh hour, after Almena and Harris accepted a deal to plead no contest. Under that agreement, Almena and Harris were to be sentenced to nine and six years, respectively, in county jail. Subtracting credit for time served, Almena could have been released in 3½ years and Harris in less than two, as opposed to 39 years in state prison if convicted in trial.

But in a stunning move, a second judge tossed that agreement after finding that Almena failed to show adequate remorse for the victims. Because the two pleas came as a package deal, Harris’ agreement was scrapped as well.

Briggs and Serra have since tried to stall or have the case dismissed. In recent months, the defense attorneys have unsuccessfully accused investigators of destroying evidence, called for the citizens’ arrest of city officials and, in Briggs’ case, asked for a six-month delay of the trial.

How long will the trial last?

Arguments over lingering motions and jury selection could delay the onset of testimony for weeks.

Alameda County Superior Court Judge Trina Thompson has carved out 12 to 18 weeks for both defense and prosecutors to present their evidence after the jury is sworn in, and may provide some time off to reduce juror hardships.

What could we learn during the trial?

Investigators were not able to determine an official cause of the conflagration, and such a revelation is unlikely in trial.

Mary Alexander, who represents victims’ families in a civil case, said many are eager to hear Almena’s and Harris’ testimony, should they take the stand.

Sue Slocum, mother of 32-year-old victim Donna Kellogg, on Monday said she was bracing herself for excruciating testimony. But in the coming weeks Slocum planned to make the two-hour drive from Salinas to Oakland as often as possible, and to book hotel rooms.

“I have to put myself into what happened to her,” she said. “I have to know.”

She wants to know where her daughter’s body was located, and why people on the second floor couldn’t get down. And she wants to know if one troubling witness account is true — that there was someone at the bottom of the stairs telling people not to come down.

“I will not say closure, it’s never about closure,” she said. “There were so many series of errors along the way. And when the trial starts, we’re going to be able to hear all that.”

Megan Cassidy is a San Francisco Chronicle staff writer. Email: megan.cassidy@sfchronicle.com Twitter: @meganrcassidy