Opening arguments have begun in the manslaughter trial for the man accused of killing 15 people in an I-95 bus crash last year.

Ophadell Williams has pleaded not guilty to manslaughter and negligent homicide. Prosecutors said he drove the bus despite being seriously sleep-deprived. The district attorney said that he'll be using phone records to show Williams was awake when he should have been resting. Meanwhile, the defense attorney says the case has no merit.

The bus Williams was driving ran off the Cross Bronx Expressway as it was returning from an overnight trip to a Connecticut casino. Williams said he was cut off by a tractor-trailer, but the National Transportation Safety Board said in June that the crash was probably caused by driver fatigue. Williams maintains that he was not fatigued at the time of the crash.

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