A Revenue Appeals Commissioner found that Independent TD Michael Lowry misappropriated around €372,000 from his own company in 2002, lawyers for the DPP told the High Court.
Senior Counsel Remy Farrell told the court it should cast a very jaundiced eye over Mr Lowry's argument that there was "nothing to see here" and it was "just a mistake".
Mr Lowry is trying to stop his trial on tax charges in relation to a payment due to his refrigeration company Garuda in 2002 which the prosecution alleges was diverted into an Isle of Man trust.
It was not declared by Garuda until 2007.
He argues the decision to put him on trial cannot be justified in the light of the Appeals Commissioner's decision that he had no personal income tax liability in relation to the payment.
Mr Lowry also claims there has been an interference with his right to a fair trial due to unprecedented interference with his case by the media.
He says the prosecution is oppressive and that the transfer of his trial to Dublin from Tipperary is a fundamental breach of his rights and punishes him for being a successful TD.
Mr Farrell said that Mr Lowry claimed he had "self corrected" the "very peculiar" 2002 transaction by declaring it in 2007.
But he said that Mr Lowry knew full well that the monies had not been earned in the previous year.
He said Mr Lowry had stayed quiet until the "Lowry tapes" came into the public domain in 2013.
He said the Appeals Commissioner had found that Mr Lowry had no personal liability for tax when an assessment was raised on a very specific basis.
But the process was still in train, he said, and an assessment could be raised by Revenue on a different basis.
He said Garuda had paid €38,000 in corporation tax in relation to the payment and had not appealed that assessment.