The Conservative MP for North Shropshire has been found to have breached Commons rules on lobbying by repeatedly using his position to promote companies he was paid by - and is now set to be suspended from Parliament for 30 days.
However Mr Paterson has rejected the findings of Parliamentary Commissioner for Standards Kathryn Stone, labelling the process biased and saying it contributed to the death of his wife.
"I lost my beloved wife of 40 years and this process was a major contributory factor," the former cabinet minister said in a 1,600-word response to the commissioner's report.
Rose Paterson, 63, took her life in woodland at the couple's home near Ellesmere on June 24 last year, in the midst of the investigation.
The inquiry was suspended for around five months on compassionate grounds following Mrs Paterson's death.
Its report has now been published, and found that the former cabinet minister's lobbying for firms he was paid a combined £111,000 a year by were an "egregious" breach of the rules.
"We will never know definitively what drove her to suicide, but the investigation undoubtedly played a major role," Mr Paterson said.
"Rose would ask me despairingly every weekend about the progress of the inquiry. The longer the investigation went on and the more the questions went further and further from the original accusations, the more her anxiety increased.
"She felt beleaguered as I was bound by confidentiality and could not discuss this inquiry with anyone else. She became convinced that the investigation would destroy my reputation and force me to resign my North Shropshire seat that I have now served for 24 years."
Mr Paterson, who has represented North Shropshire for 24 years, revealed that his wife also feared she would also be a casualty and be forced to resign her post as Chairman of Aintree Racecourse and a Steward of the Jockey Club.
"They were two roles of which she was rightly enormously proud," he said.
The Grand National, Aintree's biggest event, is sponsored by clinical diagnostics firm Randox who pay Mr Paterson £99,996 a year as a consultant. The MP was found to have lobbied for Randox and Lynn's Country Foods, which pays him £12,000 a year.
Giving evidence to the House of Commons Committee on Standards, Mr Paterson said the inquiry had had a "catastrophic impact" on him and his family.
The hearing was held in private but the evidence has since been made public and shows Mr Paterson told the committee "my family and I have no doubt that the manner in which this inquiry has been conducted played a massive role in creating the extreme anxiety that led to her suicide."
Addressing Mrs Paterson's death, the committee noted at the beginning of its report that it was "painfully conscious that Mr Paterson lost his wife in tragic circumstances" and expressed its deepest sympathy.
"We have striven to ensure that Mr Paterson has had every opportunity to represent himself as fully as possible before the committee, in person and in writing," it continued.
"We have extended deadlines at his request and we have accepted his request to be accompanied by his legal advisers and to make a formal opening statement to us. The allegations against him, which are the subject of the Commissioner’s memorandum, relate to his conduct between October 2016 and February 2020, before Mrs Paterson’s death. It is these allegations on which we are required to adjudicate, impartially, without fear or favour, and with a sole eye to the rules of the House and the requirements of natural justice."
Speaking publicly about Rose's death for the first time in October last year, Mr Paterson had told the Shropshire Star that the family was at a loss to understand her decision to end her life.
"There was absolutely no warning of what she was going to do," he said.
"Not once did I contemplate suicide as the reason for Rose’s disappearance.
“In my head I went through every possible scenario that could have happened – a heart attack or a stroke, maybe she had tripped and fallen. A branch could have fallen on her or maybe she had even slipped and gone into the brook and drowned.
“It has had a catastrophic effect. Rose will never see her grandchildren grow up, she will never know how much she was loved, how well she was regarded."