But their lawyer, retired colonel Michel Drapeau, says a potential legal claim was dropped because Cpl. Stuart Langridge's parents feared it would create the perception they were out to profit from the 28-year-old's death.
Shaun and Sheila Fynes were also worried a lawsuit would impede an inquiry currently taking place before the Military Police Complaints Commission, he added.
"We had to drop it in order to strip the department of any claim to litigation privilege," Drapeau said.
Among other things, the death certificate listed the wrong next-of-kin and other "egregious errors," which the Fynes petitioned to have changed.
The parents were not asking for compensation for their son's death, but in warning of court action they were instead trying to recover the cost associated with correcting the legal, public record as it related to Langridge, who killed himself at his Edmonton barracks in March 2008.
"They would never ask for compensation — ever," Drapeau said.
National Defence claims it had no hand in the death registration, but the family pointed out members of their son's regiment were on hand when it was filled out along with Langridge's ex-girlfriend.
The Fynes' threat of a lawsuit and the issue of solicitor-client privilege are at the heart of Defence Minister Peter MacKay's claim that the government must withhold certain documents from the inquiry commission.
Records that have been disclosed are so blacked out, they can easily be taken out of context, and the government is in "damage control and they're pushing back and it's like pulling teeth" to get information out of them, Drapeau said.
The federal government is covering the family's cost of legal representation as well as travel and expenses to attend the inquiry, he added.
But critics say it was granted "grudgingly" at the last minute before the opening of hearings.
"They certainly didn't do it with an open heart," said New Democrat veterans critic Peter Stoffer, who called on the Harper government to reimburse the family for the death certificate fix.
"The government should, with absolutely no estimation, pay that money back outside of the legal process. This is money they shouldn't even have to be suing for because (National Defence) screwed up and that cost the Fynes family $10,000."
Liberal MP Sean Casey, also a veterans critic, said "the government seems incapable of admitting mistakes. They're hiding behind solicitor-client privilege in order to justify untenable positions."
Langridge's parents accused military police of botching the investigation into his death by not pursuing a criminal negligence or even a disciplinary probe into the actions of members of the Lord Strathcona's Horse Regiment.
They say the veteran of Bosnia and Afghanistan suffered from post-traumatic stress disorder or PTSD and was pushed over the edge following a month of civilian hospital care by the military's humiliating treatment of him.
The military disputes the PTSD claim and has presented medical records that state Langridge suffered from drug and alcohol addiction.
Expert testimony before the inquiry Monday looked at the question of whether military lawyers could — or would — cover up negligent performance of colleagues.
Lt.-Col. Bruce MacGregor, a former Crown prosecutor and senior officer at the military's Judge Advocate General branch, testified that military police and investigators seek advice from uniformed lawyers before laying charges.
Much of his testimony was in the abstract and meant to lay the foundation for the appearance later this week of the military police officers who investigated the death.
MacGregor defended the sweeping use of solicitor-client privilege when it comes to investigation reports and advice that found its way up the chain of command to chief of defence staff's office — records the family maintains are crucial to understanding what happened.
"You have to have a free and frank ability to discuss certain things and sometimes an investigator might be going down a road that isn't the best legal path to take," he said.
"And you have to be able to sit there and you have to have an open and frank dialogue between the investigator and the prosecutor. If everything that is being said between and investigator and prosecutor is ultimately going to be disclosed, you're not going to get a freedom of thought."
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