Olive McIntosh-Stedman - the county councillor on trial for benefit fraud - told a jury she "simply forgot" to give all the details of her income.
McIntosh-Stedman, 65, of Williamson Way, Rose Hill, Oxford, denies two counts of dishonestly making a false statement to obtain benefit.
The jury at Oxford Crown Court heard that the retired nurse did not declare her monthly NHS pension, a savings account or the £500 member's allowance she received from the council when filling in forms to claim council tax benefit in 2002.
This led to her being paid more than £3,000 in benefit to which she was not entitled. She has since paid the money back.
As she gave evidence today, her defence barrister Rachel Drake, asked: "What's being suggested is that you deliberately omitted information so you'd get money you weren't entitled to. What do you say to that?"
McIntosh-Stedman replied: "I would say that it is not right because I made it clear that I forgot in the circumstances.
"I just forgot to fill in the form in the right way.
"I never ever wanted to be dishonest and therefore had no intention of being dishonest."
The jury heard McIntosh-Stedman had provided copies of bank statements for the account into which her NHS pension was paid when filling in the form for a second time, but had not declared the income in the appropriate box.
She said she was under some stress at the time of the alleged offences, suffering health problems and working long hours at County Hall.
She said: "It made me feel under par, under the weather and also unhappy."
In his summing up, prosecutor Hugh Williams said it was "not tenable" that McIntosh-Stedman had simply forgotten to declare the extra income.
He highlighted her degree in sociology and publishing, and involvement in several council committees, which would have required her to assimilate complex information.
He said: "It's the sort of intellect, I suggest, that would allow a person to fill in the forms for council tax benefit."
But Miss Drake said McIntosh-Stedman was not "financially sophisticated", adding that she did not know how to use cash machines, paid her utilities bills in cash and made mortgage payments by withdrawing money from one account and paying it into another account.
She said: "There's a great deal of difference between academic ability and day-to-day common sense.
"This is not a financially sophisticated person that you are dealing with.
"She doesn't run her finances in a modern and sensible way."
The jury is due to go out tomorrow to begin their deliberations.
The case continues.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article