Police called the incident a strong-arm robbery and argued that Brown had brought the same level of violence to his confrontation with officer Darren Wilson moments later.
But previously unreleased surveillance video casts doubt on whether Brown robbed the store shortly before he was fatally shot by Ferguson police officer Darren Wilson.
Jason Pollock, the filmmaker who discovered the video, says the footage shows Brown exchanging drugs for a bag of cigarillos around 1 a.m. on Aug. 9, 2014, about 11 hours before he was killed.
The video doesn't clearly show what was exchanged but shows Brown leaving behind the cigarillos.
Pollock says the video is proof that Brown did not rob the store.
Brown’s uncle, Bernard Brown, said the police lied about his nephew.
“The picture they painted of my nephew was not right. That video dispels one of the lies they were telling,” Bernard Brown told “Good Morning America” on Monday.
The convenience store, Ferguson Market and Liquor, strongly denies the documentary’s claims.
Jay Kanzler, an attorney for Ferguson Market and Liquor, said Pollock never reached out to him or his clients in regards to what’s seen in the video.
He said Pollock’s conclusions are entirely false and that the video doesn't change what happened.
"Right now to turn around and somehow blame folks that have nothing to do with this. To turn around and blame them and drag them back into it for what Michael Brown did is shameful."
Kanzler categorically denies there was some sort of arrangement between Brown and the employees.
St. Louis County police spokesman Sgt. Shawn McGuire said the department cannot confirm the authenticity of the video at this time and that the department's investigation is focused on the interaction between Brown and Wilson.