Joey Jackson is a criminal defense attorney and a legal analyst for CNN and HLN. The views expressed in this commentary are solely those of the author.

(CNN) We learned this past weekend about the existence of a surveillance video in the Michael Brown case that was previously undisclosed to the public. It was revealed at the debut of Jason Pollock's film "Stranger Fruit" at the SXSW festival.

Michael Brown died on the afternoon of August 9, 2014 after being shot multiple times by Ferguson, Missouri, Police Officer Darren Wilson . It was a highly controversial case which sparked civil unrest across the country. Outraged members of the Ferguson community marched with purpose, as did a contingent of concerned citizens in cities throughout the country. They did so to protest the seemingly endless string of black men shot dead by the police.

And now we have this latest development. In this video , Michael Brown looks to be in the same convenience store that he would later be accused of robbing some ten hours later -- seemingly engaged in a transaction with store personnel. Pollock asserts that the footage establishes that Brown was trading marijuana for a bag of cigars -- which Brown apparently left in the store, intending to pick up later. If Pollock's theory is correct, Brown would not have been robbing the store later that day, which was the police's explanation. Instead, he would have simply been claiming cigarillos that were already his.

Focusing only on whether or not Pollock's interpretation is right misses the point. The larger issue is why a filmmaker would be the one introducing this video to the public two and a half years later. Shouldn't that have been the job of the local authorities who committed to a fair, thorough, and complete investigation aimed at respecting the public's right to be kept fully informed?

At the time of the incident, local authorities promised a transparent investigation to determine whether the shooting was justified. The federal government undertook a parallel investigation shortly thereafter to determine whether, independent of any potential state charges, there was evidence of a violation of Brown's civil rights at the hands of Officer Wilson.

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The evidence subsequently revealed that Officer Wilson fired a barrage of bullets at Brown after an altercation that began at Wilson's squad car and ended on the street. Three separate autopsies were performed -- one by the County, one by the Federal Government, and another one which was independently commissioned by the Brown family. All revealed that Brown was shot six times -- once in the right eye, once on the top of the head, with the remaining four bullets hitting his right arm. There were no shots to the back, and indications that he had his hands up appeared to be false. Instead, the evidence revealed that he was facing Wilson, and even appeared to be approaching him. Accordingly, no state charges were filed. Similarly, Officer Wilson was also cleared by the US Department of Justice.

So after all this investigating, why are we finding out new information from a filmmaker?

St. Louis County Police told CNN that the video's authenticity cannot be confirmed at this time, but "if it did occur, the incident is still irrelevant to our investigation."

Really? One can only imagine what, if anything else, the public was not made aware of based upon its purported irrelevance. If investigators were quick to reveal that Brown was engaged in criminal behavior at the store, and that he had marijuana in his system, wouldn't it also be important know whether the store was engaged in any criminality of its own, or whether the cigarillos he walked out with were rightfully his?

As an attorney, I consider that information pretty relevant. But the central issue here is the crisis of confidence between law enforcement and the community, and the level of mistrust potentially generated by intentionally concealing information -- any information -- from public view.

After how hard multiple parties fought to get it, transparency in this case is important, no matter what. There were cries at the outset for the local district attorney, Robert P. McCulloch, to step aside and allow a special prosecutor to handle the case. Ignoring those concerns, he promised he could be fair and empaneled a grand jury to evaluate the facts of the case and to determine whether Officer Wilson caused the death of Brown through conduct that was either intentional, negligent, or reckless. In the end, the grand jury cleared Wilson.

And upon announcing that they did so , we learned that McCulloch provided grand jurors with an overwhelming amount of conflicting and contradictory evidence. While there is some precedent for such a presentation involving police suspects, most cases are not presented in this way.

McCulloch's actions were also called into question at the time because when Officer Wilson testified before that grand jury, McCulloch's staff questioned him with a light and deferential touch -- also a deviation from the norm for a prosecutor.

The community also raised doubts about McCulloch's objectivity when it was revealed that his father, a police officer, died at the hands of an African-American man when McColloch was only twelve years old. Nonetheless he went forward, giving the indication that he would be fair.

Reasonable legal minds can differ on these issues but still make full transparency about all aspects of the case critical.

Ultimately, the revelation of this surveillance tape does not change anything legally. Its release will not be enough for Missouri Governor Eric Greitens to appoint a special prosecutor to present the case to a new grand jury. Nor will it shift the findings of the federal investigation, which concluded there was no civil rights violation.

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But what it does is fuel concerns about the transparency of police investigations. Is the public being presented with the full scope of information, or just the information that authorities unilaterally believe we should know? Worse, is the information being presented in such a way as to shape public opinion? And if that's the case, what does it say about the agenda of a local prosecutor handling the case?

In the final analysis, the footage will continue to be a reminder of the need for a better approach. An approach that does not have local prosecutors who work with the police and rely upon the police, put in a position of prosecuting the very same officers. It's just bad form. If conclusions are going to be trusted and relied upon, there needs to be a system where the public will have faith in the process and can accept its conclusions.

As long as the complete picture of what happens is coming from filmmakers, and not investigators or prosecutors, the public will remain skeptical, the crisis of confidence will continue, and the great divide will become ever greater.

Note: a previous version of this story identified Jay Nixon as the current, rather than the former, governor of Missouri.