The trial for a years-old lawsuit challenging detention conditions in Border Patrol stations is set to begin Monday.
The Border Patrol has faced scrutiny over the past year for reportedly dangerous and unsanitary conditions in its facilities as hundreds of thousands of migrants have come to the southern border.
In Tucson, a judge is presiding over a trial for a lawsuit that was first filed in June 2015 and that targets the agency's Tucson Sector, which has eight stations in Arizona.
Attorneys say migrants are held in unsanitary and freezing conditions with no access to medical care.