STORMONT'S environment department has broken its eight-month silence to confirm it investigated former DUP minister Paul Givan for lighting a bonfire.
Officials said they had "considered the evidence available" and offered Mr Givan advice as part of a "proportional response".
It comes after The Irish News yesterday revealed departmental emails in which a senior environment official said it was "an offence".
Mr Givan faced criticism last July when he was still communities minister for setting pallets alight to mark the Eleventh Night in south Tyrone.
At the time the DUP and executive departments repeatedly refused to respond to requests for a comment.
But the internal correspondence shows how staff in the Department of Agriculture, Environment and Rural Affairs (Daera) had considered whether to respond.
The Irish News had asked Daera to clarify the legality of lighting bonfires, and whether there was any complaint or investigation about Mr Givan.
David Small, chief executive of Daera's Environment Agency (NIEA) discussed the "queries about when it is illegal to light a bonfire," asking his colleague, "Do we have a line on this?"
In response, his colleague said that "in essence lighting the bonfire is an offence".
Mr Givan lit the pyre as he attended the opening of a new Orange lodge football pitch near Augher with then First Minister Arlene Foster.
The Department for Communities provided more than £323,000 towards the Roughan pitch facility. The Orange Order said the pyre did not involve any tyres or flags.
In a statement yesterday, a Daera spokesman said: "In this particular case, NIEA carefully considered the evidence available and the circumstances of the incident.
"Consistent with our enforcement policy a proportional response was taken. This involved an advisory approach, providing advice to the individual involved, to make it clear that the lighting of bonfires, which contain controlled waste, is an offence."
The spokesman added: "Lead responsibility for bonfire management rests with the local councils and within district council-led multi-agency initiatives."
He said NIEA focuses on removing hazardous waste such as tyres, asbestos and fly-tipped waste over 20 cubic metres in volume, with councils tackling the remainder.
The statement continued: "NIEA is clear (that) a person who lights a bonfire containing controlled waste, e.g. tyres, is technically committing an offence of treating the waste (by burning) in contravention of the legislation.
"We seek to use enforcement action that is proportionate to the significance of the offence. This includes for example the level of environmental harm and the level of financial benefit arising from the offence."
SDLP Lagan Valley MLA Pat Catney said he plans to write to NIEA about the matter.
"If political considerations were taken into account, then it shows the very clear need for reform to establish a robustly independent Environment Agency," he said.
The probe emerges just months after Mr Givan faced criticism for scrapping of a £50,000 Gaeltacht bursary.
The late Martin McGuinness cited the cut among his reasons for resigning as deputy first minister.
Mr Givan later reinstated the fund, saying he did not want it to become a "political weapon".
In January the former communities minister also defended his 'community halls' funding scheme after its cost nearly quadrupled to £1.9m and it emerged most beneficiaries were from the unionist community.
Mr Givan insisted the initiative was "open to all and made no distinction based on the community identity of the organisation".
