AUSTIN (KXAN) — State Sen. Charles Schwertner is restating his innocence in an investigation into whether he sent inappropriate text messages to a University of Texas at Austin grad student.

Schwertner’s attorneys say they have a lie detector test to back up his denial.

Documents show the test was taken last Thursday. The test contained questions about the texts in question.

Schwertner, R-Georgetown, said no messages were ever sent and that he never lied about sending anything sexual in nature.

The test results show he was telling the truth, his attorneys say.

Days before that polygraph, Schwertner said he did nothing wrong regarding a report that UT was investigating his communications with the student.

Schwertner’s attorneys want the university to exonerate him immediately.

In a statement, UT spokesman Gary Susswein said, “In order to protect the integrity of the investigative process, the university does not discuss ongoing investigations.”