ALEXANDRIA, Va. (AP) — The judge presiding over the trial of a military contractor accused of contributing to the mistreatment of detainees at the Abu Ghraib prison in Iraq two decades ago speculated Wednesday that the jury may not be able to reach a verdict after it concluded a seventh day of deliberations.

“It’s a very difficult case,” U.S. District Judge Leonie Brinkema told lawyers in the case Wednesday afternoon, outside the jury’s presence. “I’m not sure we’re going to get a verdict.”

The eight-person civil jury in Alexandria has now been deliberating for more than a week, longer than the trial itself.

Three former Abu Ghraib detainees sued Reston, Virginia-based contractor CACI, which supplied civilian interrogators to the prison in 2003 and 2004.

A worldwide scandal erupted in 2004 when photos became public showing U.S. soldiers smiling while they inflicted physical and sexually humiliating punishments on naked detainees.