Local party activists, including county councillors, are being appointed by TDs to fill new State-funded jobs as parliamentary assistants.
The development has angered a number of existing Dáil secretaries, who believe they have in effect been excluded from competing for the new posts.
A new grade of parliamentary assistant has been created with a salary scale of between €34,485 and €43,751. As well as a full-time secretary, TDs can now appoint a parliamentary assistant to provide research, speechwriting, media and PR services, and to represent them at meetings and functions.
Alternatively, they can accept funding to the value of just under €35,000, or avail of a combination of the two options by taking some money and appointing a part-time assistant.
About 90 TDs, however, have indicated they will be appointing a full-time assistant, and 43 of the posts have been filled to date. A majority of TDs contacted by The Irish Times who have made appointments have chosen to hire party activists and base them in their local constituencies.
They defended the practice on the basis that, with modern technology, researchers were at no disadvantage working at locations other than Leinster House. Several also argued it was important to have someone who was familiar with the political arena.
Labour TD Willie Penrose said he had chosen to take funding of €35,000 rather than appoint a parliamentary assistant. He had used the money to hire his brother, Westmeath county councillor Johnny Penrose, to assist him in the constituency.
"My constituency officers appointed the best person for the job. No other person would be prepared to work until nine or 10 at night," he said.
Fianna Fáil deputy Donie Cassidy said he had appointed a 23-year-old Westmeath county councillor, Robert Troy, as a full-time parliamentary assistant.
Mr Troy, who was on secondment from AIB and had "excellent qualifications", would be based in the constituency but would also spend a couple of days a week at Leinster House.
"They must have an interest in the political philosophy of the party. It's also a position of very high trust," Mr Cassidy said.
Meath Fianna Fáil TD Johnny Brady said he had appointed county councillor Paddy Hill on a part-time basis. Mr Brady said he "wouldn't be too concerned" about possible critics of his decision to make a party-political appointment.
"If you want someone to do the work, no better person than a political representative. They know what's happening on the ground and know the people."
A number of existing Dáil secretaries are angered by the nature and manner of the appointments being made.
A secretary who spoke to The Irish Times claimed TDs were largely bypassing procedures agreed with Siptu. A straw poll of secretaries applying for Dublin-based posts found none had been called for interview.
The "vast majority" of secretaries, she said, already did the work reserved for the new parliamentary assistants, but at a lower rate of pay. The appointment of constituency-based party activists to fill the new roles meant the secretaries would continue to carry out research and similar work without recognition.
A spokeswoman for the Houses of the Oireachtas said Siptu had not raised any issues in relation to how the appointments were being implemented.