The allegations stemmed from a family disagreement over the will of Olwen Horan and effectively ended Mr Horan's brief parliamentary career. He was a first term Member of Parliament for NZ First in December 2012 when the claims were made, with party leader Winston Peters passed information from those who had themselves changed her will to access a greater share of inheritance.
In Parliament, Mr Peters said he had on the "initial complainant and those associated with him, evidence to support their allegations". In the wake of his call, "substantive material" was provided which left him with "no confidence in Mr Horan's ability to continue as a Member of Parliament". Mr Horan was kicked out of NZ First and Mr Peters, in Parliament, said the MP had "a duty, I believe, to resign from Parliament".
Mr Horan continued working as an MP, stood as an independent in last year's election but was unsuccessful.
Since then, the ongoing police investigation has dogged the former MP and made it difficult to secure sought-after jobs.
"I always knew that would be the result but it's a long time and it's certainly taken its toll in regards my reputation and the livelihood of my family. It's very difficult to get employment with my skill sets going through police checks when they say there's still a police investigation open."
One job sought by Mr Horan was a public posting for which he applied, supported by a minister and senior public servant. Neither referee was called and he wasn't even asked to interview for the posting. "That's the consequence of having your reputation trashed."
Asked about Mr Peters, he said: "I'd rather not talk about that man. I'm finding it difficult to forgive myself for believing in him."
Mr Horan considered his time in Parliament well spent, having been active as a local MP working for the people of Tauranga and as having influence on legislation passed in the House.
Among that was the casting vote on the legislation which "Mondayised" Anzac Day and Waitangi Day.
He had stayed involved in the political world as junior vice president of the former MPs association.
The impact of the public accusations on Mr Horan's wife Miranda and two children had also been significant, he said.
"The hurt for my children was immense. We lost certain things but not things that aren't replaceable. It's just made us stronger as a family, and more loving."
The information received by Mr Peters included Mr Horan's phone records, showing 144 calls to the TAB line in 10 months.
An hour later, he was out of the party.
Mr Horan told the Herald most of those calls were made while spending time with his mother, the two of them watching Trackside racing channel together. "Most of those days, I was lying with mum, on her bed, watching Trackside. I grew up in racing. I've had shares in racehorses. I have a TAB account. So what? So everyone who has a TAB account is an out-of-control gambler?"
The question came after the death of Olwen Horan. A hand-written amendment to Olwen Horan's will also carried the instruction to recover any money loaned by or "taken" by Mr Horan or his sister.
But a 2014 investigation by the Herald showed the will had been changed three times prior to her death, during June and July 2012. Olwen Horan died on August 3, 2012.
The changes were brought by Mr Horan's half-brother Peter Horan, a former bankrupt. It came after Peter Horan and another half-brother, sickness beneficiary Mana Ormsby, discovered before Mrs Horan's death that she had no money left from a decade-old lottery win they believed they had a claim to.
The will was changed to include a a $150,000 payment to Peter Horan which had not appeared in her earlier wills - and the clause asking for an investigation into spending from Olwen Horan's account by Mr Horan and another sibling.
Miranda Horan, Brendan Horan's wife, said disagreement among the family included the fate of her mother-in-law's jewellery. On a hospital visit on June 13, 2012, she told Olwen Horan she would record a conversation between them in which concerns about the will would be put on record.
Olwen Horan said: "I couldn't understand how Mana and Peter could change my will."
Told it couldn't be changed without her signature, she said it had happened when she removed another sibling as power of attorney to protect her from any anger Mana Ormsby and Peter Horan might have about the sibling holding the position.
Asked if she wanted the additional changes, she said: "No. I wanted things left as they were. They cannot change anything in my will."
Mr Peters has confirmed previously that Mana Orsmby was one of those who approached him with concerns. It is also believed Peter Horan passed information to Mr Peters, as did the bankrupt Colin Henderson. Mr Peters has said he took no heed of information from Mr Henderson.
