ALEXANDRIA, Va. (AP) -- A military contractor accused of contributing to the abuse of detainees at Iraq's Abu Ghraib prison two decades ago is again on trial in a federal courtroom after a long-awaited civil case earlier this year ended with a hung jury.

The retrial of the lawsuit against Reston, Virginia-based CACI began Wednesday with jury selection and opening statements. Three former detainees at Abu Ghraib sued CACI in 2008, alleging that civilian interrogators at the prison in 2003 and 2004 conspired with soldiers there to abuse detainees as a means of "softening them up" for questioning.

CACI has long denied wrongdoing. The company said its employees had minimal interaction with the three plaintiffs in the case and that any liability for their mistreatment belonged to the government, not CACI, because the civilian interrogators were acting under the command and control of the military.

The case finally went to trial earlier this year at U.S. District Court in Alexandria after 15 years of legal wrangling and multiple appeals. The trial was the first time a U.S. jury heard claims brought by Abu Ghraib survivors in the 20 years since photos of detainee mistreatment, accompanied by smiling U.S. soldiers inflicting the abuse, shocked the world during the U.S. occupation of Iraq.

Ultimately, though, the eight-person jury could not agree on whether CACI should be held liable. A mistrial was declared in May after eight days of deliberations. Multiple jurors told The Associated Press that a majority of the jury sided with the plaintiffs.

The jury indicated in notes it sent to the judge during deliberations it was struggling on a legal principle known as the "borrowed servants" doctrine.

CACI, as one of its defenses, has argued it shouldn't be liable for any misdeeds by its employees if they were under the control and direction of the Army.

Before the retrial began Wednesday, lawyers for the plaintiffs argued that CACI should be barred from presenting the borrowed servant defense to the jury. But U.S. District Judge Leonie Brinkema rejected that request.

In their opening statements Wednesday, lawyers for both sides honed in on the question of who was in control of the CACI personnel at Abu Ghraib.

"The Army controlled all aspects of CACI interrogators' work. Everything," said CACI's lead attorney, John O'Connor. "The Army, in a war, they're pretty jealous about guarding their authority."

On the other side, Baher Azmy, a lawyer with the Center for Constitutional Rights, which filed the case on the three detainees' behalf, cited passages from the Army Field Manual and from the Army's contract with CACI indicating that CACI is responsible for supervising its own personnel.

Despite that responsibility, Azmy said, CACI "turned a blind eye" to misconduct by its employees "and collected on a $31 million contract."

The trial, which is expected to stretch to next week, will in many ways be a replay of the one that occurred earlier in the year. All three plaintiffs are expected to give live testimony about what they endured at the prison, with one testifying in person and two others testifying by video from Iraq.

None of the three plaintiffs are depicted in any of the infamous photos that circulated more than 20 years ago when the Abu Ghraib scandal first broke. But they have alleged they endured similar mistreatment to what was depicted in those photos, including beatings, forced nudity and being handcuffed into stress positions.

CACI's lawyer did not dispute that there was horrific abuse at Abu Ghraib, but he did question whether the three plaintiffs in this case are being truthful about their experience. He said their current allegations are different from what they alleged 20 years ago, with an emphasis now on mistreatment at the hands of civilians as opposed to soldiers. He also said that the people who actually interrogated the detainees deny that they were mistreated.

The jury will also hear directly from a retired Army general, Antonio Taguba, who investigated the Abu Ghraib scandal.