An investigation into allegations of sexual harassment directed at Barnaby Joyce has not been able to make a finding due to "insufficient evidence".
The Australian farmer Catherine Marriott made the complaint in February, which led to Joyce to resign as deputy prime minister and leader of the Nationals.
But he was told on Thursday that after an eight-month investigation, the NSW branch of the Nationals had not been able to make a determination on the case.
"This is despite the fact that the investigation discovered that I was frank, credible, open and genuinely upset" because of the incident, "said Ms. Marriott in a statement on Friday.
An "extremely disappointed," Ms. Marriott said she was not surprised at the result because the party had no plans on how to handle a sexual harassment complaint against an MP.
He made three trips to the east coast at his expense to meet the party, and his name and confidential complaint leaked to the media.
"While it has been a huge personal expense, I was not prepared to spend this kind of behavior any longer," said Ms. Marriott.
"I am pleased that I defended what I thought was right".
Mr. Joyce retired in February after the accusations of Ms. Marriott were raised, describing them as the last straw.
He was already under pressure to resign after his affair with former staff member Vikki Campion, with whom he now has a son.
Later, Joyce said she knew she would have to resign once Ms. Campion became pregnant, but she remained despite the government bleeding to death.
Ms. Marriott said that the only positive thing about "this heartbreaking experience" has been the development by the Nationals of a much improved policy to deal with complaints.
The Nationals issued a statement on Friday revealing that the investigation was complete, but the result would be confidential.