Los Angeles County Superior Court Judge Lisa Lench agreed to delay his trial date to within 60 days after a pretrial hearing set for Jan. 25.
In a prior interview, Costa argued government officials share blame for the crash for failing to maintain runaway truck ramps along Angeles Crest Highway.
"When I lost my brakes, I was looking for a ramp. There was [sic] no ramps," he said.
He's also seeking to have the charges reduced to involuntary manslaughter, arguing he is the target of selective prosecution by government officials who hope criminal convictions will limit their civil liability for the crash.
Palmdale resident Angel Posca and his 12-year-old daughter Angelina died after Costa's truck plowed through the busy intersection of Foothill Boulevard and Angeles Crest Highway while descending the steep mountain pass.
Yanette Posca, who lost her husband and daughter in the collision, has filed wrongful death lawsuits against state, county and city agencies. She was at the court hearing Tuesday, but did not comment.
Costa has spent weeks crafting his legal defense from behind bars, but on Tuesday, he expressed confusion about legal procedures involving the prosecution's ability to review information he received in response to subpoenaing La Cañada Flintridge officials.
And when Costa asked to consult with Edward Murphy — the attorney Lench appointed last month to observe and step in as Costa's lawyer if he changed his mind about leading his own defense — he was rebuffed.
"[Murphy]'s not your lawyer. You're representing yourself, so you need to make these decisions on your own. That attorney is not here to consult with you. He is not your attorney," Lench said.
She also declined his request to submit court motions via email, rather than by handwritten notes.
"We don't do motions by e-mail," Lench said.