Guy Parent described as "scandalous" the treatment of those eligible to receive payments under the federal program, which is meant to compensate soldiers exposed to the defoliant in the 1960s.
Federal bureaucrats have denied claims of spouses using what the ombudsman described as a very narrow interpretation of cabinet regulations in order to justify their decisions.
Since early last month, the ombudsman's office has been flooded with complaints, notably from widows who were shut out of ex-gratia payments, even though some of them spent a lifetime caring for a sick loved one.
In one instance, a widow was denied payment because her husband died in a nursing home and the couple of 50 years was technically not living together.
"The definitions used by Veterans Affairs Canada would not withstand public or legal scrutiny. This is nothing short of scandalous," the ombudsman said Thursday in a toughly-worded statement.
The department has stamped a number of applications ineligible because they were received late something Parent said was unfair and he urged officials to cut families some slack.
The federal government originally set aside $96 million to compensate victims of the spray program, which took place on a military base in New Brunswick in 1966 and 1967.
The criticism caught the department off-guard and a spokeswoman for Veterans Affairs Minister Steven Blaney noted that the federal government had extended the deadline for medical diagnosis and beefed up eligibility criteria in order to make the program more accessible.
"We went beyond our initial commitment by providing additional funds to the program to ensure all those who are eligible for the ex-gratia payment receive it," said Codi Taylor in an email note.
The program comes to an end on Dec. 31 and Taylor said the minister will monitor cases to ensure fair and accurate decisions are being made.
Parent also took issue, in a year-end interview with The Canadian Press, about the federal government's restriction of a $250,000 death benefit to the families of married soldiers only.
The families of a handful of single soldiers have launched human rights complaints against the policy.
Parent stopped short of calling it a discriminatory practise, but suggested the families would likely have to launch a legal challenge in order to get satisfaction.
"This office stands for fairness," he said. "Discrimination is in the realm of the courts. So, whether it's discriminatory ... the courts will decide that."
He noted that the death benefit, introduced as part of the New Veterans Charter in 2006, was meant to recognize the emotional impact a soldier's death would have on the family.
The intention of the policy was meant to recognize those losses that are immeasurable "and that should extends to parents as well," Parent said.
"The loss is there and it's not an insurance business. It has to do with the loss of companionship and loved ones and it's just as hard when you look at fairness, the need is just as great for parents as it is for spouses and kids."
It was revealed last month that the families of four single soldiers killed in Afghanistan have filed discrimination complaints with the Canadian Human Rights Commission.
Their attempt to challenge the policy was given a boost by the Royal Canadian Legion, which called the practise of excluding single soldiers from the benefit, discriminatory.
Veterans Affairs has consistently argued that the benefit was meant to help the survivors of married soldiers adjust to civilian life. Officials have said single soldiers who want to leave something behind can take out extra life insurance.
A military legal expert agreed with Parent and said the most likely way the matter will be settled would be through a constitutional challenge. Retired colonel Michel Drapeau said families could petition to have the veterans charter declared unconstitutional on the basis of discrimination.