A shop clerk told the court he believed the note Mr Floyd had paid with was fake and that he appeared to be on drugs but could carry a conversation.
Mr Floyd’s May 2020 arrest and death sparked global protests about over-policing and racism.
Moments after Mr Floyd left the shop, his deadly encounter with police began.
It ended with Mr Chauvin pressing his knee into Mr Floyd’s neck for more than nine minutes before he died.
Mr Chauvin, 45, denies charges of murder and manslaughter. Defence lawyers have indicated they will argue that 46-year-old Mr Floyd died of an overdose and poor health, and the force used was reasonable.
Observers of the trial say Wednesday’s footage may be an attempt by prosecutors to deal with the allegation that drugs played a part in his death.
Shop employee Christopher Martin, 19, told the court he briefly interacted with Mr Floyd as a customer inside Cup Foods shortly before his arrest.
He said Mr Floyd “appeared to be high” because he struggled to respond to a simple question, but he was lucid enough to able to hold a conversation. He described Mr Floyd as “friendly and approachable”.
In the shop’s surveillance video, Mr Floyd can be seen laughing, talking to people, and walking around.
Mr Martin told the jury he had sold Mr Floyd a packet of cigarettes and received a counterfeit note as payment. Mr Martin described knowing the bill was fake by its colour and texture but added that Mr Floyd “didn’t seem to know it was a fake note”.
He said he had considered letting the shop deduct it from his wages instead of confronting Mr Floyd but then decided to tell his manager. Another employee went on to call the police.
Mr Martin, who witnessed the arrest, said he felt “disbelief and guilt” because “if I’d have just not taken the bill, this could have been avoided”.