New Zealand First MP Brendon Horan is under investigation, for allegedly dipping into his late mother's bank account.
The 51-year-old first term MP is alleged by his brother Mark Ormsby to have taken the money over a period of 10 years.
Most of it was withdrawn between 2007 and 2009.
Mr Horan's 87 year-old mother Olwyn died in August with less than $3000 in her bank account.
It once held more than $250,000.