Officers will have to re-take a recent Dallas police sergeant promotions exam following an internal affairs investigation that revealed ethical violations in the test-taking process.

According to a memo released by Dallas Police Chief Renee Hall, officers who took the exam will have to take a new test "due to possible ethical violations that compromised the integrity of the process."

"I understand this is disappointing and the department will work to ensure a new assessment center is done as quickly as possible," Chief Hall wrote.

The announcement comes on the heels of WFAA Rebecca Lopez's report in November. In order to become a sergeant at the Dallas Police Department, you have to be tested. Officers who score higher get promoted faster.

Some officers used a company called, Rank and File Development Group, to help them prepare for the exam. WFAA confirmed that through public records. It was apparently owned by a high-ranking officer, Major Latoya Porter. Multiple sources said Porter was one of three high ranking officers who were allowed to look at the test and assess it before it was given.

As a result, Dallas police launched an internal affairs investigation.

Sources at the time told WFAA that Porter was under investigation for charging officers hundreds of dollars for information that may have been privileged.

WFAA heard from Porter's attorney, Zach Horn, before our original story aired. "ANY Allegations that she was giving anyone answers or any kind of unfair advantage ARE categorically false," Horn said.