SEATTLE (AP) — New documents in a lawsuit say the substitute teacher who claimed she warned school officials of the impending 2014 mass shooting by a student at Marysville-Pilchuck High School may have actually kept the information to herself.

The Seattle Times reports the disputed efforts by Rosemary Cooper to inform officials of the threat will be argued in court Friday in determining whether Cooper remains a defendant in the lawsuit.

Cooper's attorney David Schoeggl claims Cooper is immune from liability because she made a good-faith effort to report the information she had.

The parents of the dead and injured students allege there is no real evidence Cooper told anyone, and that her medical records indicate she's guilt-ridden because of it.

Four students were killed and a fifth critically injured when Jaylen Fryberg opened fire on them before killing himself.