Watch Nakamoto's report here

The letter from Mona Hardin, Greene's mother, lambasts Cain and likens the agency to a "gang" for its efforts to conceal what happened to Greene. 

"Doug Cain belongs in jail; instead, your agency promoted him to Lieutenant Colonel and increased his pay," the letter reads in part. "But for the brave actions of Troopers like Carl Cavalier and Albert Paxton who spoke out against my son's injustice, I would still believe that my son died in a single-car crash. The world now knows that narrative to be untrue."

Greene, a Black man, was beaten and tased after a wreck in the Monroe area back in 2019. Family members were told Greene died in a crash, but video showed he was still alive when troopers dragged him from his vehicle after it crashed.

Click HERE to read the full letter from Mona Hardin.

"Knowing that this man could participate in the cover-up of her son's brutal murder and still be at work, that's almost something you can't make up," Eugene Collins with the Baton Rouge NAACP said. "That's why the NAACP is sitting here today calling for Lieutenant Colonel Doug Cain's resignation."

State Senator Katrina Jackson represents the district in Monroe where Greene died. She wants to see Cain and others who played a role in the cover-up fully investigated. She said she's read the notes that were referenced in the WBRZ Investigative Unit story Wednesday night and believes investigating troopers Albert Paxton and Scott Brown who noted the cover-up.

"I don't have confidence in State Police to investigate itself," Jackson said. "Not even for employees...until we know who all was involved in all these cover-ups. It's not just Ronald Greene."

Collins said he's spoken to Mona Hardin who has waited nearly three years for justice for the death of her son. He said this is like a slap in the face to her.

"Mr. Cain should not be in that role. Every time you go to work you are spitting in the face of that family, spitting in the face of Ms. Mona Hardin who has traveled to Louisiana time and time again expecting a grand jury indictment and that has not come."

The governor's office released the following statement Thursday in response to the WBRZ Investigative Unit's story: 

"The Ronald Greene case is under investigation and the Louisiana State Police continue to cooperate with all aspects of the investigation. The Governor expects nothing less and continues to have confidence in the leadership at Louisiana State Police."

Read the statement from the Legislative Black Caucus below.

As it has done in the past, the Louisiana Legislative Black Caucus (LLBC) continues to monitor the details and investigation surrounding the tragic and senseless death of Mr. Ronald Greene.

The LLBC maintains its belief that there are systemic problems and serious concerns that need to be addressed within the Louisiana State Police (LSP).

The LLBC membership is aware of and disturbed by recent information shedding more light on the involvement of Lieutenant Colonel Doug Cain in the investigation surrounding Mr. Greene’s death.

As we process this information, our membership remains vigilant in our commitment to seeking needed policy changes as well as transparent communications from Louisiana State Police and accountability. We also continue to stand with Mr. Greene’s family in their fight for answers and justice.

Additionally, a letter was drafted by the LLBC to the Department of Justice requesting the federal government do a methodical investigation and review of the pattern and practices of LSP with results to be expedited to the LLBC. We will not stop until justice is served.

Cain was promoted to Lieutenant Colonel when Kevin Reeves abruptly quit his position in October 2020 following numerous controversies exposed by WBRZ.

Watch Nakamoto's full report on WBRZ at 6:00

Greene, a black man in Monroe, was brutally beaten and died in May 2019. State troopers originally told Greene's family that he died in a crash. However, body camera footage that came to light showed the truth. 

INVESTIGATOR'S CASE NOTES RELEASED IN FULL

The new documents WBRZ received include all of Trooper Albert Paxton's case notes from the Ronald Greene death investigation. A few pages of those notes were leaked to WBRZ last year, but Cain's name was not mentioned in any of them.

The notes in their entirety say Cain "blew off" the investigating trooper and made it known to others that he did not trust Paxton.

According to Paxton's notes, both he and Scott Brown wanted Chris Hollingsworth arrested a week after Greene died. That never happened. Instead, more than a year passed before the case came to light. Months later, Hollingsworth died in a single-vehicle crash hours after he was served termination papers from the agency in the fall of 2020.

Paxton spoke to Cain on Dec. 23, 2020 about his concerns. Paxton mentioned Trooper Kory York committed batteries on Greene.

"He says York has already been punished and we are not going back," Paxton noted Cain telling him.

On another occasion, during meetings with prosecutors, it was noted that Cain did not want a high-ranking trooper who hid evidence to be prosecuted and even "appeared angry" that the district attorney was considering it. It involved the highest ranking trooper on scene the night Greene was killed. Lt. John Clary's body camera footage was hidden from investigators until it was leaked out.

On May 20, 2021, Cain and others met with District Attorney John Belton.

The notes read, "Cain tells the DA Greene screamed out because a taser probe was being removed. Doug Cain defends Clary. Doug Cain does not want Clary prosecuted... Doug Cain appears angry the DA is even thinking about it."

Documents notated in investigative reports show that was not the truth. Ronald Greene was already unresponsive when taser probes were removed from Greene. That is also backed up by body camera videos and the investigation into his death.

PAXTON CALLS STATE POLICE A CRIMINAL ORGANIZATION

Trooper Paxton called State Police "a criminal organization." Paxton announced his retirement from the department last week and testified at the capitol that investigators were now targeting him.

"I'm being investigated because I won't participate in the cover-up, I won't hide evidence and won't lie," Paxton told lawmakers last month.

Following the release of a few pages of the notes last year during a WBRZ interview with Trooper Carl Cavalier, Paxton said he was called to an internal affairs interview.

"They are investigating my personal notes. How did Carl Cavalier get my notes? LSP doesn't care what they detail. LSP is mad Carl has exposed a cover-up. LSP wants to know why I kept them and who I gave them to. I am protecting myself. LSP is looking to blame someone. I wouldn't badmouth Cavalier. This is when I became a target."

STATE POLICE RESPONDS

We reached out to Louisiana State Police for a response to this story. The full response is below.

We cannot speculate on the context and inference of Sgt. Paxton’s personal investigative notes.  Additionally, this matter is still under investigation by investigating authorities.  However, our department has fully cooperated with all aspects of the investigation.  

We routinely engage in discussions with investigators and prosecuting authorities on the circumstances surrounding incidents and investigations.  The investigation into Mr. Greene’s death began the very night of the incident with evidence having been provided to state and federal investigators during the entire process. 

LSP personnel will continue to provide assistance into the ongoing review of the incident and we will continue to offer our full cooperation to all investigating authorities.  

Thomas came under fire last October when an audio recording surfaced where she claimed $5 million was missing from the bus company. The conversation in the recording is between Thomas and former employee Elijah Pipersberg. Pipersburg oversaw policy at the bus system and references CATS CEO Bill Deville in the recording.

"What has he [Deville] fixed since he's been here without you?" Pipersberg is heard asking.

A woman responds in the recording. WBRZ confirmed through multiple sources the voice is Pearlina Thomas.

"Ahh, covering up the bulls*** from the previous board members and financial folks worth $5 million gone missing," the female voice says.

Following the WBRZ Investigative Unit publishing the recording, Thomas did an interview to clear the air.

"Poor choice of words," Thomas said. "It wasn't 5 million, and he didn't cover it up. I was trying to remember the context of which that happened, and I can't. In 2018, there were some things going on where it was miscoded and the agency wasn't doing timely drawdowns of our federal funds."

WBRZ asked what she meant in the recording, with the number $5 million being so precise. Thomas again insisted no money is missing.

"I take full responsibility for what I said," Thomas said. "Even though I misspoke. It was inappropriate, and it was a huge learning lesson for me and that the delineation of authority of our organization is important."

The WBRZ Investigative Unit asked CATS about Thomas' termination. A spokesman said he could not comment because this is a personnel matter.

Thomas declined to comment at this time, citing the advice of her attorney.