The grievance hearing for William Fleming High School Principal Susan Willis ended Thursday after nine days of testimony on whether she inappropriately manipulated the schedules of dozens of students to curve the school's performance on state-mandated tests.

An attorney for Willis said after the hearing that accusations of Willis' involvement in schedule manipulation were an attack from Roanoke schools Superintendent Rita Bishop.

"This was a concerted effort led by Rita Bishop to get Susan Willis," James Thorsen said in a statement. "Taxpayers should be outraged and should ask for a complete investigation of Rita Bishop and her staff."

Bishop, meanwhile, said there was no evidence that system administrators knew about schedule manipulation at the school.

"There is not one shred of truth that anyone at central office manipulated anything," Bishop said.

A Virginia Department of Education report released in June accused Willis of manipulating some students' schedules to keep them from taking Standards of Learning tests, which may have boosted the school's performance on the federal benchmarks of No Child Left Behind.

The hearing with a three-person panel -- consisting of a high school volleyball coach, a human resources director and a lawyer -- began in late August and was originally scheduled for two days.

The attorneys will present written closing statements by Oct. 5, and the panel will make a recommendation to the school board, which has the authority to hire and fire a principal, as late as Nov. 4.