THE MURDER CASE against the man accused of assassinating conservative activist Charlie Kirk last year is headed for trial and the defendant could face the death penalty if he is convicted.

Utah District Judge Tony Graf on Tuesday sided with prosecutors who said they had “overwhelming” evidence that Tyler Robinson shot Mr Kirk once in the neck as the ally of President Donald Trump spoke to a crowd of thousands last September in Orem, Utah.

One of Robinson’s lawyers entered a not guilty plea on his behalf following Judge Graf’s decision.

Robinson’s lawyers tried to block a trial, arguing prosecutors failed to show Kirk’s shooting placed others around him at risk of death.

That is an aggravating factor under the law that makes Robinson eligible for the death penalty.

Mr Kirk’s family called the ruling “an important step in our family’s pursuit of justice”.

“Every step in this process carries the weight of all that Charlie’s murder has taken from his family, especially his children who will grow up without their father,” the statement said.

“We are grateful to all who have continued to pray for us, support us, and stand with us through a year of unimaginable grief.”

Prosecutors said Robinson shot Mr Kirk from a rooftop more than 400ft away and could have easily missed, injuring or killing other people.

Judge Graf had the option to send the case to trial on a lesser charge of murder, which carries a minimum sentence of 15 years and a maximum of life in prison, said Steve Burton, director of the Utah Defence Attorney Association.

The judge said his decision to approve the aggravated murder charge was based on “the documented position of several individuals in and around the canopy area” where Kirk was speaking, among other factors.

“These circumstances support a reasonable inference that defendant was aware that other individuals were positioned near Mr Kirk when he fired,” the judge said.

The hearing on Tuesday in Utah state court came after prosecutors in July spent five days presenting what they said was “overwhelming” evidence that Tyler Robinson killed the conservative activist while he was speaking at an open-air event on a college campus.

The 23-year-old defendant turned himself in a day after the shooting at Utah Valley University last September.

Robinson’s lawyers have not offered alternative theories for Mr Kirk’s death and have focused instead on blocking the case from proceeding to trial and trying to get the death penalty taken off the table.

Mr Kirk’s parents, Robert and Kathryn Kirk, entered the heavily secured facility arm in arm before the hearing at the Fourth Judicial District Courthouse in Provo. Erika Kirk was seated beside them.

The family stepped out during part of a prosecutor’s argument that described the shooting.

A few local members of Mr Kirk’s organisation, Turning Point USA, arrived with signs expressing their support for Erika Kirk but were told by security that they could not have them on the court property.

Robinson had no visible reaction to the arguments.

His mother Amber Robinson watched from the courtroom gallery and his father Matt Robinson listened with his head bowed.