Elijah Pickett, 18, is charged with second-degree murder, robbery, burglary, and criminal use of a weapon, in regards to an incident at a St. Joseph home in August, 2011.
Pickett is accused of shooting Brian Ulmer three times in his home.
Appearing before a jury for the first time, Pickett remained expressionless as Buchanan County Prosecutor Dwight Scroggins delivered his opening statement, giving a detailed account of the evidence that implicated Pickett as the triggerman and a timeline of how the incident occurred.
The prosecution alleges that Pickett shot Brian Ulmer in the head a point-blank range when Ulmer attempted to grab Pickett's leg.
The defense told jurors they plan to show how the prosecution's witnesses and evidence are not credible.
The prosecution's first witness was 21-year-old Kasey Hall, who has already pleaded guilty to second-degree murder in connection with the 2011 incident that left Ulmer dead.
Hall received a 20-year sentence, and is required to testify as part of a plea deal.
Hall testified that he, Pickett, and Xavier Johnson, entered Brian Ulmer's home the night of the shooting.
The jury heard Hall say all three men had guns, and that Hall was first to leave upon shots being fired.
When cross-examined by the defense, Hall told jurors he was tagging along with Pickett and Johnson to "go get some weed."
The prosecution's second witness was Cassandra Richardson, a woman living in a house on N. 15th Street in St. Joseph the night of Brian Ulmer's death.
Richardson testified that she saw a White SUV followed by a green Pontiac Grand Am park across the street from her house after dark the August, 2011 night the homicide occurred.
According to her testimony, three black men got out of the green car and walked out of sight down the street. It was later she heard there was a shooting at the Ulmer residence, a block away from her house.
Scroggins did point out to the jury that the green Grand Am became one of the key pieces of evidence that detectives used to implicate Pickett in the attempted robbery and homicide.
Tina Kellogg, Brian Ulmer's fiance at the time of his death, was the last witness to testify in Tuesday's morning court session.
Kellogg was one of four people in the living room when it's alleged that Pickett, Johnson, and Hall entered the house.
Kellogg told jurors that a tall black man she later identified as Elijah Pickett was the one who demanded money, and ultimately pulled the trigger and shot Brian Ulmer three times.
Her testimony described her trying to perform CPR on Ulmer before paramedics arrived.
Through her detailed account of that night's events, Ulmer's friends and family were heard audibly showing emotion in courtroom.
Kellogg told the court she tried unsuccessfully to revive her fiance. It was not until Ulmer was at the hospital that he was pronounced dead.
In the weeks after Ulmer's death, Kellogg told the court she had identified Pickett in a photo lineup provided by detectives. She said she was "almost positive" it was him upon looking at the photos.
After Judge Patrick Robb called a lunch recess, Prosecutor Dwight Scroggins told KQ2 he expects Pickett's trial to last until at least Wednesday afternoon.
"There's still plenty of evidence to get to," Scroggins said.