LIBERTY, Mo. (AP) — The family of a Black Kansas City teenager who was shot by a white man after he mistakenly knocked on the man’s door are frustrated with the prosecutor’s handling of the case, attorneys for the family said Thursday.

The complaints came after a preliminary hearing for 84-year-old Andrew Lester was set for Aug. 31-Sept. 1 and just days after a Clay County judge approved a request by Lester’s attorney to seal documents in the case.

Lester has pleaded not guilty to first-degree assault and armed criminal action in the shooting of Ralph Yarl, who knocked on Lester’s door on April 13 while trying to pick up his young brothers, who were at a home a block away.

Civil rights attorneys Benjamin Crump and Lee Merritt said in a Zoom news conference that they had previously asked Clay County Prosecutor Zachary Thompson to step aside and let Jackson County Prosecutor Jean Peters Baker be named as a special prosecutor in the case but that Thompson “adamantly” refused.

The family is upset that Thompson did not more aggressively challenge the motion to seal court records and that the preliminary hearing was delayed for 90 days, which Thompson did not object to in court.

“We continue to encourage the prosecutor to zealously prosecute this case as he would had the dynamics been different,” Crump said. “We don’t want any different form of justice or policy because we have a young teenage Black kid shot by an older white man.”

Thompson’s office said in a statement that the focus of his office “remains squarely on following the law and achieving justice.”

The shooting drew international attention amid claims that Lester received preferential treatment from investigators after he shot Yarl.

President Joe Biden and several celebrities issued statements calling for justice for Yarl.

Lester admitted that he shot Yarl through the door without warning because he was “scared to death” he was about to be robbed by the Black person standing at his door. He remains free after posting $20,000 — 10% of his $200,000 bond.

The teen’s father, Paul Yarl, said after Thursday’s hearing that he hopes Lester eventually serves jail time.

“The shooter was going to kill Ralph,” Paul Yarl said. “It’s obvious, right? He shot him twice. His intent was to finish him off. So yeah, we need justice for that.”

Ralph Yarl, who has celebrated his 17th birthday since the shooting, suffered gunshot wounds to his head and wrist and continues to recover at home.

His mother, Cleo Nagbe, said he is trying to get back some normalcy in his life.

“The longer we stretch this out, the longer it takes him to get that little bit of normalcy he needs to spend his teenage years just doing teenager stuff … Ralph needs to be the teenager that he needs to be that Lester is stealing away from him,” Nagbe said.