Jeffrey Epstein's death may close the book on his criminal case, but it will do little to bring closure for the victims and leaves myriad unanswered questions.

Epstein, a financier and convicted sex offender, was facing two federal charges — one count for sex trafficking a minor and one count of conspiracy to sex traffic involving underage girls — and potentially up to 45 years in prison.

He had pleaded not guilty and was awaiting trial when he was found unresponsive in his cell on Saturday and later died in hospital.

It will never be known what more a criminal trial might have revealed about the horrible crimes he's alleged to have committed. But there is a chance we may yet learn about the wider network that influenced and enabled his actions, and what connection it has to the rarified halls of power, money and influence in which Epstein lived.

Here are four key questions that arise from Epstein's death.

How did he die in federal custody?

The most serious question around the 66-year old's death is how it could happen at the Metropolitan Correctional Center, one of the most secure facilities in the U.S.

"I was appalled, and indeed the whole department was, and frankly angry to learn of the MCC's failure to adequately secure this prisoner," U.S. Attorney General William Barr said Monday.

Barr said the Department of Justice is looking into "serious irregularities" at the facility that are "deeply concerning and demand a thorough investigation." He said the FBI and the DOJ Inspector General are doing just that.

Within a day of those comments, a shakeup in prison management was underway. The warden was reassigned to a regional office pending the outcome of the dual investigations while two MCC correctional officers assigned to guard Epstein were placed on administrative leave.

U.S. Attorney General William Barr said Monday that there were 'serious irregularities' at the federal jail where Epstein was found dead in his cell this weekend as he awaited trial. (David Grunfeld/The Advocate/The Associated Press)

The MCC is an imposing 12-storey building in lower Manhattan that routinely houses high-profile defendants being tried in New York. Among the infamous inmates who've spent time there were crime boss John Gotti, convicted financier Bernie Madoff, Sheik Omar Abdel Rahman, convicted in the 1993 World Trade Center bombing, and most recently, drug kingpin Joaquin "El Chapo" Guzman.

The results of an autopsy on Epstein have so far not been made public. Epstein's apparent suicide comes about two weeks after he was found unconscious in his cell with bruising on his neck from an apparent suicide attempt or possible assault.

The multimillionaire had been placed on suicide watch on July 23, but according to the Wall Street Journal, sometime before the end of the month his lawyers had requested he be taken off it.

Epstein was reportedly in "special observation status," which required checks at 30-minute intervals and a constant cell-mate. Reports suggest neither of those protocols were followed leading up to Epstein's death and that he hadn't been checked for several hours.

"We will get to the bottom of what happened and there will be accountability," Barr said.

The union representing correctional workers at the facility says overwork may have played a role, and issues of chronic under-staffing at the facility are nothing new. The Associated Press reports that one of the guards covering Epstein was working a fifth straight day of overtime, and another was working mandatory overtime.

It's also come to light that one of Epstein's guards the night he died in his cell wasn't a regular correctional officer.

Serene Gregg, president of the American Federation of Government Employees Local 3148, told The Washington Post that one of the guards was a fill-in who had been pressed into service because of staffing shortfalls.

What does this mean for the investigation?

While the criminal case against Epstein goes to the grave with him, the larger investigation around sex trafficking and who enabled him will continue, federal prosecutors at the Southern District of New York said over the weekend.

Epstein's charges included a conspiracy count, which prosecutors promised to continue to investigate. The SDNY statement also included a call for any victims to come forward.

"It's very clear that [Epstein] didn't do this alone, and the Southern District, I do believe, will be indicting other people who helped him run this sex trafficking ring, and those people will face justice," Elie Honig, a former state and federal prosecutor, told CBC News.

The Metropolitan Correctional Center, where Epstein was being held. (Don Emmert/AFP/Getty Images)

"It may not be quite as satisfying as seeing Jeffrey Epstein himself face justice, but these other people are not going to escape, and we will have more information about [Epstein's] operations," Honig said.

The attorney general also promised to pursue "anyone who is complicit, any co-conspirators."

One of the key targets could be Ghislaine Maxwell, a British socialite and daughter of newspaper magnate Robert Maxwell. She's been accused of being Epstein's co-conspirator and allegedly recruiting young girls for him.

There are also lingering questions about Epstein's financial dealings. Last week, the billionaire behind Victoria's Secret, Leslie Wexler, accused Epstein of misappropriating "vast sums" of his fortune while managing his personal finances more than a decade ago.

What happens to Epstein's accusers?

For Epstein's accusers, his death snatches away their chance to face him in open court, but a number have said they'll continue to seek justice through civil lawsuits against his estate.

"They are disappointed that once again they have been cheated out of an opportunity to see Jeffrey Epstein held appropriately accountable by the criminal law for his actions," lawyer Jack Scarola told CBC Radio's As It Happens. He represents five women who say they were abused by Epstein.

"They certainly do not grieve his passing, but they regret that information that he has that may contribute to holding others responsible for their participation in his crimes may have died with him," Scarola said, adding his clients hope Epstein's death may allow others to feel safe to come forward.

How much of Epstein's estate may be available to victims is still an open question. A recent court filing listed his assets at more than $559 million US.

That included cash and investments, as well as properties in New York, New Mexico, Florida, France and his private island in the U.S. Virgin Islands.

Sigrid McCawley, an attorney representing one accuser, said in a statement that "the reckoning of accountability begun by the voices of brave and truthful victims should not end" with Epstein's death.

New York state prosecutors had already signalled in their indictment of Epstein that they would seek to forfeit his $56-million New York apartment — a process that can continue, says former federal and state prosecutor Carl Bornstein.

The federal government could also forfeit other properties used in the commission of the crimes of which Epstein is accused. Bornstein says that money could be available for Epstein's accusers to pursue in a civil case.

"I think the U.S. Attorney would want to make what's recovered part of a fund for the victims to proceed against," said Bornstein, now a professor at the John Jay College of Criminal Justice in New York.

Will we ever learn Epstein's full story?

The key to learning more about the accusations around Epstein can be found, in part, in documents released last Friday from a now-settled defamation case involving Maxwell and one of his accusers, Virginia Giuffre.

Giuffre alleged that when she was 15, she was a victim of sex trafficking and abuse at the hands of Epstein and Maxwell that went on between 1999 and 2002. More than 2,000 pages of documents from that case were unsealed, and they include disturbing allegations of abuse involving Epstein and others.

The documents also contain accusations involving high-profile names like New Mexico Gov. Bill Richardson, former U.S. senator George Mitchell, Prince Andrew and lawyer Alan Dershowitz. All have denied any wrongdoing.

While not fundamentally reshaping what we know about Epstein, the documents do provide more depth, and more names, said Adam Klasfeld with Courthouse News.

And more documents could be coming. A hearing in the Giuffre case is scheduled for September 4, though it's not clear if a decision on releasing more information will come at that time, he said.

"The flood of information, long suppressed about the case, is not going to abate," Klasfeld said. "It's basically just starting."