Ferguson, Missouri (CNN) Video that a filmmaker says shows Michael Brown in a Ferguson, Missouri, store engaging in a purported drug exchange hours before he was killed is nothing more than a "poorly edited snippet," the prosecutor who investigated the case said Monday.

Director Jason Pollock, whose film "Stranger Fruit" debuted at the South by Southwest festival in Austin, Texas, over the weekend, claimed the video shows that Brown did not rob the store before his deadly confrontation with Ferguson police officer Darren Wilson. Rather, it shows the 18-year-old exchanged marijuana for cigarillos with the clerks, Pollock told CNN.

St. Louis County Prosecuting Attorney Robert McCulloch called Pollock's assertions "just stupid" during a Monday afternoon news conference.

"What this guy's putting out is just nonsense," he said.

An attorney representing the convenience store concurs with the prosecutor's account.

A description of the video was made available in a police report, the prosecutor said, and investigators viewed the video less than a week after Brown was killed, to determine whether Brown had tried to steal something when he visited the store.

"There was no relationship between them," Attorney for Ferguson Mart says about #MikeBrown. The filmmaker just wants "15 minutes of fame." pic.twitter.com/a1ThFWidX9 — Nick Valencia (@CNNValencia) March 13, 2017

What McCulloch's team determined is that Brown entered the store by himself, picked drinks from a cooler and asked for cigarillos, he said. The clerks bagged the goods and Brown put something on the counter, which the clerks examined, McCulloch said. That's all captured on the video Pollock released.

What's missing from Pollock's video -- as a result of a "very poor job of editing in the first place" -- is a clerk talking to Brown, and Brown putting the bag back on the counter, removing something from the counter and exiting the store, McCulloch said. The video then shows the clerks put the cigarillos back on the rack and the drinks back in the cooler, he said.

"There was certainly an attempt to barter for these goods but the store employees had no involvement at all in that," the prosecutor said. "When he left, they put everything back on the counters where they belonged and went about their business."

McCulloch said: "There was no transaction between Mr. Brown and the store employees."

The video was "not relevant or material" to Brown's death and was never presented to a grand jury, McCulloch said, explaining why it wasn't part of the trove of evidence he publicly released on November 24, 2014.

Attorney releases video

CNN viewed the video released by the convenience store's attorney. In it, Brown can be seen placing an item on the counter. A clerk picks it up, smells the item and appears to place it back on the counter. Another clerk then picks it up and smells it, and appears to put it back on the counter. It is unclear what happens to the item after that point.

A third clerk then places Brown's store merchandise -- what appears to be cigarillos and soda -- in a grocery bag on the counter. Brown picks up the bag, and as he walks away, there appears to be a discussion. Brown returns to the counter, hands back the grocery bag and walks away.

One camera angle from behind the counter appears to show a clerk taking the box of cigarillos out of a grocery bag and putting it back. That clerk then appears to hand the other items in the bag to another clerk who walks off camera with them.

The entire exchange lasts one minute and 55 seconds.

It is unclear what item Brown placed on the counter, and who possessed that item when he left the store.

Jay Kanzler, the attorney for the convenience store, asserts that his client says the item Brown placed on the counter was a bag containing marijuana. Pollock, the filmmaker, also says that Brown was trading marijuana for a bag of cigarillos, though CNN cannot confirm the contents of the bag.

Small demonstration

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After word of the video surfaced, about 100 protesters gathered at the store Sunday night, forcing it to close, and gunshots were heard before midnight, but none of the protesters appeared injured, the St. Louis Post-Dispatch reported. A Ferguson police officer suffered a broken nose when a woman punched him in the face during an arrest, the paper reported.

During media rounds Sunday and Monday, Pollock told reporters Brown and the Ferguson Market and Liquor had an agreement. There was no robbery, he said.

Pollock suggested that had this footage been released, it would've altered the narrative that Brown was shot after robbing the store. Instead, he claimed, investigators lied and "wanted to make Mike look bad, so they put out half a video to destroy his character in his death."

The filmmaker further alleged, "This is a shady store. We've asked a lot of people in this community. You can buy weed (marijuana) at the store."

Brown's father, appearing with Pollock during one interview, said the video shows his son "was not in the wrong," and he'd like to see the case reopened.

In another interview, Brown's father said he was "still broken, hurt, mad" watching the video more than two years later.

"I just want the public to know that he wasn't ... a bad guy, how bad they actually demonized his name and the family because of what they showed," he said. "I'm just happy that the public can see... with their own eyes."

Police have said the footage is irrelevant to their investigation. Investigators have previously said Wilson initially stopped Brown for walking in the street , not because the store reported a robbery.

Attorney: Footage manipulated

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The new footage, captured about 11 hours before Wilson fatally gunned down Brown, shows Brown placing a small bag on the counter. Two of the clerks pick it up and appear to sniff it.

The clerks then give Brown a bag with cigarillos, which he takes, but he then turns around and gives it back to them before leaving. According to Pollock, it was common for residents to barter with the clerks, and the younger clerks did not want an older clerk to know what they were up to.

So, in the widely publicized video released after Brown's death, Brown was not stealing cigarillos, but rather, retrieving them after he'd left them in the store earlier, the filmmaker said. According to Pollock, the clerk who Brown pushes in that video is the older clerk, who was not aware the other clerks had given Brown the cigarillos as part of the barter exchange.

Pressed on whether he had edited the video, Pollock, a former creative director for documentarian Michael Moore, stood by his claims: "We show the entire exchange. We show the exchange from behind the counter. ... Anybody that sees it sees what happens."

"The behind the counter shot is the shot we wanted to show the world because that shows the exchange," Pollock said in another interview with CNN. "We didn't want to show the front camera shot because you can't see it."

The title for Pollock's film comes from a song popularized by Billie Holiday protesting the lynchings of African-Americans across the South. One verse of the poem describes "black bodies swinging in the Southern breeze, strange fruit hanging from the poplar trees."

'My clients did nothing wrong'

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Kanzler, who represents the store and employees, refuted Pollock's story and told CNN the video was edited to omit a clerk throwing a bag back to Brown.

"My clients did nothing wrong," Kanzler said. "They love the people of Ferguson and truly want to get on with their lives."

Kanzler was present at the market during the protests Sunday night. Video from the scene shows him speaking to people as protesters shout at him.

In an interview Monday with CNN, Kanzler said it's important to see the roughly four-minute video "because you see the whole transaction."

"He's saying there was a deal. There was no deal. There was no pot left behind. There was no understanding," the attorney said. "They gave the pot back and there was this argument."

Kanzler has said the video is "not new" and that the full video was handed over to police, the FBI and the Brown family "very early on."

The officer, who resigned from the Ferguson Police Department after the shooting, has claimed Brown assaulted him and there was a struggle over his gun. Brown took off running, according to police, only to turn around and charge at Wilson, who opened fire, fearing for his life.

"This has caused significant harm to this community again," Kanzler told reporters.

The store turned over the DVR, Kanzler said, and he received the video months later. He later gave copies to attorneys for the city and to Brown's family because the family had filed a lawsuit, he said. Brown's family has had the video since October, according to the attorney.

In April 2015, Brown's family filed a civil lawsuit against the city of Ferguson under Missouri's "wrongful death statute."

No bartering or trade, a clerk says

In an interview Monday with CNN, a store clerk who was working that night said Brown asked if they "trade here." The clerk, who was said he was afraid to go on camera, claimed he told Brown no.

The clerk said Brown "just grabbed the cigarillos and tried to leave."

The clerk also claimed he said to Brown that if he didn't give the items back, he would call the police.

The clerk claimed no trading or bartering took place.

"He left with nothing," the clerk said. "I took everything back."

Police: Video 'irrelevant'

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The Ferguson Police Department did not respond to CNN's request for comment. The St. Louis County Police Department said of the video that they "cannot confirm its authenticity at this time." However, the department said the new footage isn't pertinent to its investigation.

"If it did occur, the incident is still irrelevant to our investigation because our department investigated the encounter between Michael Brown and Darren Wilson," the county police said.

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