Social Development Minister Nelson McCausland ignored officials who warned against meeting DUP colleagues to discuss the axing of Housing Executive contracts with the firm Red Sky.
Rejecting the advice of senior civil servants, he took part in a meeting discussing the setting up of a new company that could potentially take over the terminated work.
The disclosures came at the Assembly committee monitoring Mr McCausland, which is investigating allegations of political interference in the Housing Executive.
It was the first major evidence session since all Assembly parties except the DUP backed the committee's assertion that Mr McCausland deliberately misled MLAs. It heard from DSD permanent secretary Will Haire.
Neither a representative of the administrators nor from the Housing Executive was present at the meeting between Mr McCausland and party colleagues, the committee heard.
Mr Haire made clear Mr McCausland had been advised against agreeing to the meeting requested by DUP MLAs Robin Newton and Sammy Douglas because of the ongoing contractual and legal issues between the Housing Executive and Red Sky.
Questioned by committee chair Alex Maskey, Mr Haire said: "One puts advice to ministers... but ministers have the right to decide." Sinn Fein's Mr Maskey said it was difficult to understand how a permanent secretary could be overruled. Mr Haire said: "I have a role to put advice, but it is duty of the minister to take the decision."
Quizzed by Jim Allister, senior DSD official Jim Wilkenson agreed the meeting had discussed setting up a new company that could take over the Red Sky contracts. The TUV leader suggested the minister had attempted to act in a way that would give Red Sky time to reform, and was in effect promoting the commercial interests of a company.
Mr Allister then asked Mr Haire: "Have you ever before encountered a situation where a minister wanted to interfere in a contractual matter?"
Mr Haire, who is also the department's accounting officer, replied: "That may be more to do with my experience... this was the first time it had happened in my experience."
Mr Maskey commented: "It is clear that advice was given but not accepted by the minister."
Mr McCausland has already insisted: "I can assure you categorically that I have never sought to influence any contracts, neither this nor any other contract, indeed neither do I have any role in this. This is, as I have always advised, an operational matter for the Housing Executive alone, they make the decisions."
The DSD committee is focusing on the allegations surrounding the Red Sky maintenance firm
An £8m-a-year deal had been terminated in 2011 amid allegations that the east Belfast firm had overcharged for work on NIHE properties.
The company admitted that it mistakenly charged the Housing Executive for work on two apartment blocks.
Ultimately the firm, which employed 450 people, was put into administration.