A U.S. soldier charged with murdering an Afghan civilian this year has no right to use grisly photographs of the dead man during a preliminary hearing in his case, Army prosecutors said in a court filing obtained Tuesday by The Associated Press.

Last month the Army Court of Criminal Appeals took the unusual step of halting the prosecution of Pfc. Andrew Holmes, of Boise, Idaho. The court ordered prosecutors to respond to Holmes' arguments that refusing to let him present the photos was tantamount to closing the proceeding in violation of his right to a public trial.

Holmes is one of five soldiers from Joint Base Lewis-McChord, south of Seattle, charged with murdering three Afghan civilians for kicks during patrols in Kandahar Province this year. Holmes is accused of direct participation in the first killing and of conspiracy in all three.

The Army has closely guarded dozens of gruesome but unclassified photographs seized during its investigation — including one that reportedly shows a soldier stabbing a mangled Afghan corpse. It has refused to give copies to defense attorneys for fear they could be leaked to news organizations and incite opposition overseas.

During Holmes' Article 32 hearing last month to help determine whether his case will proceed to a court-martial, prosecutors sought to have one investigator testify about the contents of photos relevant to Holmes' case.

One of the photos showed Holmes posing as he grabbed the corpse by the hair and held up its head, the investigator said.

Holmes' attorney, Dan Conway, objected, comparing the government's refusal to present the photos to closing a public hearing.

He also argued that there was no way he could cross-examine an investigator about photos that were not in evidence, which would violate his client's constitutional right to confront witnesses against him.

Conway also sought to introduce the photos on behalf of his client, saying they could show that Holmes' weapon didn't cause the victim's wounds.

In a response filed with the appeals court last Thursday, Army prosecutors argued that the right to a public trial doesn't apply to such preliminary hearings and that the Army isn't obligated to turn over the photos at this stage of the prosecution.

The Army did not respond to a request for a copy of its filing, but Conway provided one to the AP after he received it.

"Failure to turn over or disclose documents do not render an Article 32 hearing closed, and appellant cites no rule, statute or case precedent supporting such a proposition," the prosecutors wrote.

Furthermore, the Army said, if Holmes believes that evidence was improperly withheld during the hearing, he should take it up with the judge at his court-martial — not with the appeals court.

Conway said he would file a response within two weeks.

"The Article 32 investigation is supposed to be a search for truth, and any search for truth that excludes exculpatory evidence is a complete charade," he said.

Eugene Fidell, president of the National Institute of Military Justice, said he found the Army's arguments unpersuasive.

His organization plans to file a friend-of-the-court brief on Holmes' behalf within a few days, he said.

(This version corrects name of National Institute of Military Justice.)