Testimony is expected to begin this week in the trial of Aee Shawn Mathews, the man accused of pulling the trigger in the shooting death of 26-year-old William Underwood, a Colorado Springs-area rapper also known as FYL Jackk.

On the evening of Sept. 17, 2019, Underwood was confronted outside his aunt’s home during his birthday party by an assailant who shot Underwood 18 times, including seven times to the back of the head.

Investigators would not make an arrest in the shooting until March 7, 2024, when both Aee Shawn Mathews, 27, and Derrick Bernard, 36, were charged in his death.

Prosecutors believe Bernard, also an area rapper, wanted Underwood dead due to an ongoing feud. Bernard was in custody of the Department of Corrections in 2019 at the time of Underwood’s death because he pleaded guilty to weapon possession by a previous offender in 2018, where he was sentenced to 32 months in prison, according to court records.

But in a series of messages and phone calls, prosecutors allege Bernard instructed Mathews in coded language to kill Underwood for him.

Both men have pleaded not guilty to the murder.

Bernard was tried for the murder in November of this year. He represented himself in court, and lost, being found guilty by the jury of first-degree murder. The verdict was guilty on all three counts of first-degree murder, and the sentence was life in prison without the possibility of parole.

Mathews’ jury trial began Friday with jury selection, and is expected to continue through Wednesday.

Both Bernard and Mathews are also awaiting trial on accusations of attempted murder of two Colorado Springs police officers, stemming from a 2022 incident.