UPDATE: Judge dismisses both charges against former Chattanooga police officer Karl Fields

Karl Fields testifies during a hearing for Cordalro Strickland in Judge Don Poole's courtroom in Chattanooga on Wednesday, Oct. 24, 2014.

UPDATE: Judge Barry Steelman just dismissed both charges against Fields, saying the state couldn't prove beyond a reasonable doubt the former police detective concealed any evidence in the James Works case.

He ruled before jurors began deliberating on Fields' case, agreeing with a defense motion to dismiss the case.

Previous story:

photo Karl Fields
photo Hamilton County District Attorney General Neal Pinkston

District Attorney General Neal Pinkston knew a potentially exonerating video of an alleged rape existed when he called the Tennessee Bureau of Investigation to look into a Chattanooga detective's concealed it, special prosecutors said today.

Karl Fields now faces tampering with evidence and official misconduct charges for allegedly never including that video of James Leon Works Jr. having consensual sex with a woman in an Aug. 20, 2014 case file to Pinkston's office. He concealed the video to maintain a sexual relationship with the alleged victim, who said Works raped her in a hotel room in May 2014, special prosecutors have argued.

Those special prosecutors took aim today at Pinkston, who testified Thursday Fields and his supervisor, Bill Phillips of the Chattanooga Police Department, told him about the video before Fields was suspended in Sept. 4 2014.

Prosecutors have a constitutional responsibility to share exonerating evidence with defense attorneys, said Pinkston, who could not recall the specific dates he spoke with Fields and Phillips.

"You have to understand - some days I could get 40 or 50 phone calls, and I don't keep a log of everyone," Pinkston said. "But I remember a number of phone calls between Fields and Phillips about this case."

Pinkston, who took office as District Attorney General on Sept. 1, 2014, said he asked the TBI to look into Fields when the alleged victim's attorneys told him about a number of inappropriate text messages between Fields and the woman. In the letter, he mentioned there was a "potential criminal action" into Fields over the alleged video.

But he did this knowing Fields had already mentioned the video and his concerns about it, special prosecutor Alyson Kennedy said.

"If it's your testimony that either Sgt. Phillips or detective Fields or both had advised you in some form prior to Sept. 1 about the existence of this video then you knew those allegations aren't true," she said of the letter Pinkston wrote to the TBI Sept. 8, 2014.

"Are you accusing me of not being honest?" Pinkston asked. "Is that what you're doing?"

Pinkston said he followed the law, including the facts as he knew them at the time.

I'm told that a video exists by detective Fields, Sgt. Phillips," Pinkston explained. "I've heard there's a video from two other lawyers. But I try not to assume anything. Sometimes allegations are made and it's not true. So until I have a copy of the video - it may or may not exist."

Pinkston said Thursday he put the evidence into Works' case on Sept. 9, 2014.

Since the state rested its case Thursday afternoon in Criminal Court, defense attorney Tidwell has been calling witnesses, including Pinkston. This is the fourth day of Fields' trial.

Attorneys met with Judge Barry Steelman in chambers Thursday evening and today to discuss an issue. Steelman said today special prosecutors asked to further question Pinkston on the witness stand, seemingly to impeach his testimony for the defense.

"I don't really see the letters as impeaching General Pinkston," Judge Barry Steelman said while considering another defense motion to dismiss the charges. "He in a broad way said somebody come look at Fields."

He has not ruled yet.