The convenience store cashier who sold cigarettes to George Floyd and took a counterfeit $20 bill in return took the stand at Derek Chauvin's murder trial.
Christopher Martin, 19, said that as he stood on the curb a short time later, his hands on his head as watched Floyd's arrest, he felt 'disbelief and guilt'.
'If I would have just not taken the bill, this could have been avoided,' Martin said. 
Cashier tells of guilt over role in events that led to George Floyd's death