Ms Lockhart said the apology raises more serious questions about the conduct of the Commission and has called for a fully independent, preferably Judge-led, inquiry.

Commenting on the issue, Ms Lockhart said: “Let us shine some light into the dark corners of the Parades Commission.

“In the currency of the High Court Drumcree case, the Secretary for the Commission told Mr Justice McAlinden, under oath, that I had simply failed to respond to a request to make submissions on Drumcree. The Commission sought to major on this to discredit me, and the case.

“At the time this evidence was given, it now transpires that the Commission were well aware that, in fact, no email had been sent to me at all.”

The MP added: “Not only this, but the same person, who on behalf of the Commission, told the Judge I had not responded, was the very person who had discovered I had not received the email -  a mere matter of days before providing this misleading (at best) evidence to a High Court Judge.

“This may seem bad enough, but the Secretary to the Commission then went on to say, in his retrospective justification for misleading the court, that he did not think my involvement would be a relevant issue in the case, despite the fact it was he who had sought to introduce the issue to bolster the Commission’s case.”

Ms Lockhart continued: “All of this occurred on 3rd July, and the Commission were aware that had they admitted this (and the many other errors) then, their Drumcree Sunday determination would have fell there and then.

“But they brazened it out to get past that weekend, to be sure they denied the Portadown District their Drumcree Sunday parade.”

“This is a significant issue, and one for which there must be accountability,” explained Carla Lockhart MP. “I have received a formal written apology from the Chair, but mere words are regrettably not enough. 

“This is not about me, but about the integrity and trust in a public body, charged with making the most important of decisions on cultural issues in Northern Ireland.

“I had held off on highlighting this serious issue until the case had passed, lest it interfere with the court process. But now it is important this matter is placed in the public domain.

“When public officials provided evidence to the court in public law proceedings, the court and the public must be able to trust this is truthful and transparent. The Commission, putting it at its lowest, fell well short of this standard.”

Ms Lockhart added: “I am further deeply concerned about what else has occurred in the WhatsApp chats, and whether there is other damming material being concealed.

“It is only a fully independent, and ideally, Judge-led inquiry into all these issues that can get to the truth. As Mr Justice McAlinden said, the errors of public bodies should be exposed to the public, with no attempt to conceal or hide things.

“We need accountability and transparency. The public, and elected representatives, must be fully sighted as to what has gone on in this Commission. We will not rest until we secure that transparent accountability.”