The jury is deliberating Thursday afternoon in the second-degree murder trial of Brandon Chase of Jefferson City.Thursday morning, Cole County Prosecutor Mark Richardson told jurors they should convict Chase of robbery, murder and armed criminal action in the last April's death of Keith Mosley, Jr. Defense attorneys said the prosecutionâ??s case is built on what somebody said, not what somebody saw. Testimony wrapped up Wednesday after Chase took the stand in his own defense. Chase was the only witness called by the defense. He claimed he did not know other men were planning to rob the victim.Jefferson City Police said the shooting happened during a drug deal turned robbery on Buena Vista Street in April 2012.Chase said he tried subtly to warn the others in the room, including Mosley, that something bad was about to happen.The prosecution argued Chase was not carrying enough money to go through with the drug deal.The jury is expected to have their decision Thursday afternoon.