LAKE STEVENS — The father of a Lake Stevens Marine who collapsed and died while being punished by his superiors plans to contest a report claiming that his son’s death was caused by a pre-existing heart condition.

An internal military investigation concluded that Lance Cpl. Dustin Canham’s superiors broke rules when they had him do push-ups and other exercises as punishment for chipping another man’s tooth, but that Canham’s death was not due to hazing.

Canham, a 2004 graduate of Lake Stevens High School, took part willingly to avoid a black mark on his record, Lt. Gen. Samuel T. Helland, the commander of U.S. Marine Corps Forces Central Command, said in a summary provided to Canham’s father, Mark Canham.

“This whole thing is suspect,” Mark Canham said.

Dustin Canham didn’t have a heart condition, he said. Mark Canham said he has hired a lawyer and plans to work with other families who have lost loved ones in situations the military has called accidents.

Mark Canham and Devyn Canham, Dustin’s 19-year-old widow, believe the Marine may have been hazed or forced to work out until he died.

The Naval Criminal Investigative Service is conducting its own investigation.

Canham, 21, died March 23, after two superiors took him into a tent at Camp Lemonier, a U.S. base in the rocky desert of Djibouti, in the Horn of Africa. In letters shortly after his death, the Marines told Canham’s family he collapsed while exercising, but the letters didn’t explain why Canham was in the tent with two superiors.

The approximately 300-page investigative file on the case, which includes some statements Canham’s fellow Marines gave to NCIS, makes clear that the use of physical training was not authorized. “Extra military instruction” — the assignment of extra tasks — may be given to correct a Marine’s shortcomings, but not as punishment, Helland wrote.

“Despite the physical training session being conducted outside the parameters of applicable orders, procedures and regulations, the training was not harsh nor abusive and was not the cause of death,” Helland wrote.

Earlier that afternoon, Canham and a private were playing catch with a rock, the documents say. The private told investigators that he looked away just before Canham threw it, and the rock hit him in the mouth. It chipped his tooth, but the injury did not require medical attention.

When platoon Sgt. Jesus Diaz, 24, of Bakersfield, Calif., heard about the incident, he brought it to the attention of a staff sergeant, who noted that formally recording it in Canham’s record could hinder his promotion to corporal.

The staff sergeant recommended that Diaz give Canham a choice of receiving a mark on his record or performing physical training, and Canham — who was working toward a perfect score on his next fitness test — chose the latter.

“(The staff sergeant) and I both felt LCpl Canham was a good Marine, and did not want to have to write him up for this incident,” Diaz told an NCIS investigator in a signed statement.

The names of the staff sergeant and other witnesses were redacted in the file, but the Associated Press independently identified Diaz as well as the other superior who brought Canham into the tent, Cpl. Richard Abril, 28.

Diaz and Abril said they told Canham to get three bottles of water, and that Abril, being Canham’s “fire team” leader, performed the exercises alongside him. With Diaz watching, Abril and Canham did a routine called the “daily seven,” involving 30 push-ups followed by leg lifts and other core-body work.

About 20 push-ups into the second round of exercises, Canham “stopped, went to his knees, sat back on his hips, leaned up against a rack and passed out,” Abril wrote in a statement to investigators. It had been only three minutes since the exercises started, he said.

Diaz ran for help as Abril started performing CPR until emergency responders arrived, they wrote.

More than an hour of resuscitation efforts proved unsuccessful. An autopsy determined that Canham had a mildly enlarged heart with a thickening of the left ventricular wall, which left him vulnerable to cardiac arrest.

The AP reported last month that the pathologists who performed the autopsy were not told that Canham was exercising or that he was being punished when he died, and they did not consider heat exhaustion as a possible factor.

That issue is not discussed in the file. However, a cardiologist who tried to resuscitate Canham, Navy Capt. Michael J. Curran, noted in a letter to investigators that “it is extremely difficult, if not impossible, to witness a patient exercising to the point in which they induce a primary cardiac arrest in a healthy, normal heart. With continued exercise and serial fatigue, most patients will no longer be able to exercise well before they have cardiac abnormalities.”

The 8th Provisional Security Company, in which Canham served, instituted several changes following his death, including adding training about extra military instruction.

In light of Canham’s death, a corporal in the platoon complained about Diaz, and supervisors agreed that Diaz should be “removed from his leadership position,” investigators wrote. He was reassigned to the armory at Camp Lemonier.

Mark Canham said he wants to see for himself if Diaz told the truth to investigators.

“If he could tell me to my face what happened in that tent, then I’d believe it,” he said.