An employee who exposed questionable training practices at former state training agency FAS is no longer being given work duties, a telephone or the use of a computer in her office.
The chairman of the Public Accounts Committee (PAC), John McGuinness, told the Dail that whistleblower Una Halliday was being persecuted and humiliated.
Ms Halliday, a training coordinator with FAS's successor Solas, raised concerns about the marking of courses in 2009.
Her allegations, many of which were proven by an internal audit, ultimately led to a nationwide review of FAS's course provision.
She later filed a complaint alleging she was victimised by elements within the organisation and last year received a settlement payment of close to €100,000.
But Solas has now accused her of breaching a confidentiality clause linked to that settlement and has threatened it will take legal moves to recover the money.
Mr McGuinness, a Fianna Fail TD, told the Dail that Ms Halliday was currently off work due to illness, yet Solas was seeking to interview her.
"I ask Solas, FAS or whoever is responsible there now, to stop the persecution of this woman," said Mr McGuinness.
"She, like many others who blew the whistle, now go to their offices and are given no work, telephone or computer.
"They are humiliated every day they go in and are shouted at in front of other employees. Their rights are ignored."
Mr McGuinness continued: "I ask whoever is listening and who is responsible that they would leave this woman alone. They should deal with the matter in a far more constructive manner, and not in the way they are pursuing it at present.
"Above all, they should respond to this parliament and a request that has been made by a member of the Oireachtas to stop and treat that person like a human being."
Mr McGuinness's intervention came during a debate on the Protected Disclosures Bill, which aims to protect whistleblowers.
He pressed Public Expenditure Minister Brendan Howlin to personally intervene in Ms Halliday's case on behalf of the Government.
"He should make a direct intervention and ask for some respect. The woman is out sick and her family are deeply concerned," said Mr McGuinness.
Solas did not respond to the TD's comments last night. A spokesman said: "We will not be making a statement on this matter."
Its chief executive Paul O'Toole is expected to face questions on the issue when he appears before the PAC next Thursday in connection with Solas funding for Rehab.
Ms Halliday exposed instances where people on FAS courses were given pass grades in exams even though they should have failed.
A FAS audit found that a tutor had falsified the results. It also found evidence that assessment materials had been manipulated on other courses.
FAS terminated the training company's contract and launched a nationwide review of its courses.
The episode badly damaged the reputation of FAS qualifications internationally and ultimately signalled the death knell of the agency, which has now been broken up.