A former DUP minister has admitted he was involved in an anonymous leak to his own department's top civil servant in a bid to ease pressure on his party over Stormont's botched green energy scheme.
Simon Hamilton told a public inquiry into the Renewable Heat Incentive (RHI) that his behaviour in January 2017 was "highly unorthodox" and was "not his proudest moment".
The RHI was designed to encourage businesses and farmers to switch to eco-friendly wood pellet boilers by offering a subsidy to buy the sustainable fuel source.
But errors in its design meant applicants were paid more than it actually cost them to buy pellets - so they were effectively incentivised to burn as much as they could to turn a profit, leaving Stormont exposed to a potential £490 million overspend.
Ex-economy minister Mr Hamilton told the inquiry panel that he and his former special adviser John Robinson were behind the sending of copies of emails to the media and the permanent secretary of his department, Dr Andrew McCormick.
Mr Hamilton said he and his adviser met to discuss what to do with the emails before Mr Robinson then sent them anonymously to Dr McCormick in an envelope. Mr Robinson also sent them to the media, the former minister said.
"I don't think it was my idea," Mr Hamilton told the inquiry.
He added: "I accept this looks highly unorthodox - it is highly unorthodox."
Mr Hamilton sought to explain the episode by stressing it happened during the "worst time" of his political career, when the DUP was facing a "febrile" onslaught of allegations about corruption linked to RHI.
The emails indicated that two civil servants had given advance warning to industry figures of planned changes to the RHI scheme aimed at reducing the inflated tariff pay-outs to applicants.
Mr Hamilton said the 2015 emails were "pretty explosive" and countered the public narrative that DUP advisers, in particular Dr Andrew Crawford, were principally to blame for a spike in applications to the RHI before the tariff reductions came into effect.
Inquiry chairman Sir Patrick Coghlin said Mr Hamilton had used "the cloak of anonymity to take the pressure off a Spad (special adviser Dr Crawford)".
"I wouldn't imagine it would be one of your proudest moments?" he asked.
The MLA replied: "You're right, it is not my proudest moment.
"It is one of many things that I regret around this period. The only thing I offer in mitigation, and it is not a wonderful thing to offer in mitigation, is the atmosphere we found ourselves in - it was an incredibly difficult time, we were all under extreme pressure and that sometimes leads you to do things that at other times, with clear and rational thought, you might not have otherwise done."
Sir Patrick responded: "Well that's what you take on as responsibility as a minister."
Mr Hamilton said relieving pressure on Dr Crawford and the wider party was "certainly the objective" but he insisted the aim was not to deliberately "slap" that pressure on specific other individuals.
"I would set it in the context of the time we found ourselves in where we - we being the party - are being assailed on all sides, we are getting hit left, right and centre every day, it seems like every hour of every day, and there isn't much to fire back, there isn't much to combat these allegations with," he said.
"Here is something that is very different to anything that we had had before. Some of arguments that were thrown back before were quite technical or they got lost - this was pretty straightforward to understand.
"Hence we did what we did."
Inquiry panel member Dame Una O'Brien questioned how Mr Hamilton's actions could be in line with Stormont's ministerial code.
Fellow panellist Dr Keith MacLean suggested Mr Hamilton had fired "very sensitive information about individuals" into the public domain to "point the finger" on people outside of his party.
Earlier, the former minister expressed regret on not exerting more pressure on officials to find ways to limit the damage wreaked by the RHI.
Mr Hamilton was pressed on efforts by his civil servants to reduce expenditure in 2016, after the scheme had closed to new applicants.
He conceded an October 2016 report drafted by officials was "flawed" and "shoddy" and took longer than it should have to complete.
Mr Hamilton told the inquiry his "heart sank" when he realised the exercise had been conducted by the same officials who had originally not spotted the fatal flaws in the RHI.
Months later Mr Hamilton did finally outline plans to cut the overspend - by controversially reducing the rates the executive had pledged to pay applicants over long-term contracts.
But by that stage the political crisis over the RHI had effectively reached the point of no return, with the powersharing executive having imploded when the late Sinn Fein deputy first minister Martin McGuinness quit in protest at the DUP's handling of the affair.
Mr Hamilton was challenged by the inquiry panel why he had not done more to ensure the October report was up to scratch and produced on time.
"I did push, I did ask, but I regret I didn't push even more," he said.