Stormont departments are facing legal bills relating to the RHI inquiry of almost £5.5m, new figures have revealed.
The inquiry was set up to investigate the mismanagement of the Renewable Heat Incentive after the cost of the scheme spiraled out of control.
The RHI scheme was set up in 2012 to boost uptake of eco-friendly heating systems. However, flaws in its regulations meant those businesses on it could profit the more they used the heating system.
The Department of Finance has published its legal costs as well as those relating to the Executive Office, the Department of Agriculture, Environment and Rural Affairs (DAERA), the Department for the Economy.
The figures, which related to 2017/18 and 2018/19, show that the Department of Economy is facing a total bill of £3.98m.
The next highest is the Executive Office, with a bill of £1,090,229.
The Department of Finance has to pay £372,401 and DAERA will pay £20,290 - bringing the total legal bill for Stormont departments to £5,462,920.
This covers the total cost of legal advice and representation for individuals who were in the relevant departments during the period being examined by the RHI inquiry.
The inquiry designated a number of organisations as "core participants", including the Department for the Economy and the Department of Finance.
The inquiry, which was chaired by retired Court of Appeal judge Sir Patrick Coghlin, is yet to publish its findings. However, it is expected to report next month.
It was set up to examine why the scheme did not contain the same cost controls as the one in Great Britain.
Its 111 days of oral hearings ended in October 2018.
The cost of the inquiry itself which has run on longer than was first anticipated - it has been estimated - is expected to cost up to £6.7m.
The Department of Economy has also been involved in lengthy legal battles with those RHI boiler owners who are battling against the cuts to the scheme's tariffs. Those who took up the scheme were guaranteed a level of payments for 20 years.