DAMIEN MEYER via Getty Images An hold man holds his stick on April 3, 2012 in Blois, central France. AFP PHOTO DAMIEN MEYER (Photo credit should read DAMIEN MEYER/AFP/Getty Images)

The Canada Revenue Agency is demanding thousands of dollars from a B.C. senior, who suffers from dementia and Parkinson's disease, for failing to declare a foreign pension on his tax return.

Arne Sorbo, 88, forgot to declare the small Norwegian pension he receives on his 2011 tax return. The CRA discovered the mistake following a reassessment, and slapped him with a fine.

Now the retired Certified General Accountant, who for decades prided himself on getting the numbers just right, says he feels "rotten."

"I used to do income tax for seniors at no charge and I don't think they meant to lie. I think they're honestly trying to give a correct answer to questions, and I think the same thing applies here," said Sorbo.

"I thought my return was correct. That's what I thought. I don't know where I went wrong, or what happened."

Sorbo's tax troubles do not end there. The CRA took another look at his 2013 tax return as well. The agency deemed he could not claim a spousal deduction for his wife because she is under the age of 65.

In fact, his wife is 79-years-old and also suffers from dementia.

"That's unbelievable that the tax department should be that far out," said Sorbo.

Now Sorbo is facing almost $12,000 dollars in tax, penalties and interest.

Taking the taxman to task

Sorbo's son Michael, himself a Certified General Accountant, stepped in to help his father sort out the tax nightmare. However, even he says he can't get answers from the CRA.

"I keep having to open the file, write a new letter, and then get a new assessment. That's really frustrating going back to my dad and saying, 'I haven't been able to resolve this,'" he said.

Sorbo has sent the CRA a copy of his mother's passport to prove she is, indeed, over 65.

He has also asked the agency to invoke its own "fairness provision," which allows penalties to be waived for certain individuals like the elderly and the ill.

So far, Sorbo says the response from the CRA has been robotic and insensitive, and that it's nearly impossible to get the same agent on the phone twice.

The CRA has told him it will take up to 15 months to get a final decision on his father's case.

"When would it take 15 months to look at a simple fairness provision on a simple issue? Why should it take that long?" said Sorbo.

Meantime, the interest on the $12,000 dollar penalty is growing.

"It drags on and on, and I don't know if they want you to pay the balance, so they sort of wear you down."

CBC News contacted the CRA to discuss the Sorbo's case, but it declined to comment due to confidentiality issues.

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