HOUSTON, Texas (KTRK) — Tywana Gilford Mason is the fifth and final person charged in what Harris County prosecutors say is a teacher certification scandal that spanned several years.

According to court documents, Mason used his role at the Houston Education and Training Center to register teacher candidates for their certification test and then let them leave.

READ ORIGINAL: Five people charged in alleged teacher certification cheating scandal, Harris County prosecutor says

Police say they then allowed a man identified as Nicholas Newton, assistant principal at Booker T. Washington High School, to take the test on their behalf.

According to court documents, Vincent Grayson, the basketball coach at the same school, also known as “Kingpin,” bribed her and paid her about $125,000.

“The best we can see is that he has made $1.9 million from this scheme. There is almost certainly more than that because there is cash and it is harder to trace,” said Mike Levine, chief of serious crimes at the Public Corruption Division of the District Attorney’s Office.

Court documents say this happened more than 400 times and primarily involved aspiring teachers from the Dallas area.

Grayson is one of three HISD educators who are part of this circle.

“We will fire any teacher who fraudulently passed their exam and will work to ensure that a highly qualified teacher takes their place,” said Alexandra Elizondo, Chief of Public Affairs and Communications for the Houston Independent School District.

Mason is accused of engaging in organized criminal activity.

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