BANGOR, Maine — A Superior Court jury will resume deliberations today in the murder trial of a Prentiss man accused of killing his best friend after snorting cocaine.

The jury of seven men and five women must decide whether Joseph Dumas, 49, is guilty of murder or manslaughter. Dumas admitted that on Nov. 8, 2007, he shot and killed Mario “Sonny” Litterio, 70, of Prentiss near a camp on Tar Ridge Road in Prentiss where Dumas was working.

To find Dumas guilty of murder, jurors must conclude that he acted intentionally or knowingly when he pulled the trigger. If jurors found that he acted recklessly or with criminal negligence, they could return a verdict of manslaughter.

If convicted of murder, Dumas faces a sentence of 25 years to life and none of it can be suspended. The maximum sentence for manslaughter is 30 years and a portion of it may be suspended.

The case went to the jury about 11:30 a.m. Thursday after closing arguments and instructions from Superior Court Justice Michaela Murphy. An hour later, the jury asked that testimony given Wednesday by psychologists for the prosecution and the defense be read back.

It took much of the afternoon for the court reporter to locate and the attorneys to agree on which specific sections of testimony the jury wanted to hear. The read-back of the questioning of defense psychologist Diane Tennies of Bangor and Shawn Willson of Kansas, the psychologist for the prosecution, will begin this morning. It was estimated Thursday that it would take about 90 minutes to complete the read-back.

Tennies’ testimony is at the heart of the defense’s argument that Dumas is not guilty of murder because he was suffering from a cocaine-induced psychosis when he pulled the trigger. Willson disagreed with Tenneis. She said that Dumas’ cocaine use did not prevent him from engaging in goal-oriented conduct.

“The evidence is overwhelming in this case,” Assistant Attorney General Andrew Benson said in his closing statement, “that Josepeh Dumas took two separate guns and fired those [four] shots into the back and the head of Sonny Litterio with [Litterio’s] gun, then took his own black powder rifle and finished him off.

“Does that sound like reckless conduct?’ Benson asked. “No. This is all goal-directed conduct.”

Defense attorney Richard Hartley said in his closing argument that Dumas snorted nearly an eighth of an ounce of cocaine before the shooting. The psychosis induced by the drug kept Dumas from being able to act intentionally or knowingly, he said.

“Joseph Dumas didn’t intentionally shoot Sonny Litterio and the evidence tells you that,” Hartley told the jury. The question you need to answer is: When Joseph Dumas stepped behind his best friend and started shooting, was his conscious objective to cause his friend’s death?”

Family and friends of the defendant and the victim were in the courtroom Thursday but declined to speak to reporters.

Prosecutors in the Attorney General’s Office do not comment on cases until a verdict has been announced.

“The jury is thinking long and hard about the issue of Joseph Dumas’ cocaine use,” Hartley said after court adjourned Thursday. “They are taking their obligation seriously.”