The Glasgow club said yesterday they have submitted a complaint to the Scottish Legal Complaints Commission (SLCC) which has been passed to the Law Society of Scotland.
The news comes after Mr Bain’s legal team won an order to freeze nearly £500,000 worth of Rangers’ assets at the Court of Session on Tuesday.
This was part of a personal claim relating to his departure after Craig Whyte took over the club from Sir David Murray in May.
Rangers’ London-based legal firm, Collyer Bristow, confirmed the complaint had been lodged.
Glasgow-based Levy & McRae said yesterday that it had sought specific advice from the Law Society over any potential conflict of interest at an earlier date, and that Collyer Bristow had been kept informed of this.
Levy & McRae, which also represents The Herald, said as it had only represented Rangers in disciplinary matters and did not act as the club’s corporate lawyers, there was no conflict.
A spokesman for Rangers Football Club said: “We can confirm that a complaint was submitted to the Scottish Legal Complaints Commission and has been forwarded on to the Law Society of Scotland, raising a conflict of interest matter.
“The club’s lawyers have been informed that the matter is being investigated.”
Peter Watson, senior partner at Levy & McRae, said last night: “Levy & McRae are aware of this and have been in touch with the Scottish Legal Complaints Commission and Law Society of Scotland to draw their attention to the fact that Collyer Bristow, representing Rangers Football Club, were advised that no conflict of interest existed and that this was the opinion, not just of Levy & McRae, but also two separate Queen’s Counsel, and that the opinion, when reached by both QCs, was supported by Bruce Ritchie of the Law Society of Scotland.
“For some reason, it appears that Collyer Bristow failed to pass this information on to the SLCC and that has been brought to the SLCC’s attention and, if necessary, any procedure which is commenced will be challenged in the Court of Session.
“Collyer Bristow have been asked why this omission took place and so far have not replied.”
Mr Watson added that his firm represented Rangers over several years during Sir David Murray’s ownership of the club, but said: “We only acted on specific projects including Uefa disciplinary proceedings, and were not their corporate lawyers. There is no conflict of interest in us representing Martin Bain.”
Asked about the response from Mr Watson, Gary Withey, of Collyer Bristow, said: “This is a matter before the Law Society of Scotland and we have every confidence that it will be investigated fully.”
Neither the Law Society of Scotland nor the SLCC would comment on the case for legal reasons.
Earlier this week Lord Hodge said the club faced the possibility, rather than “actuality or probability”, of insolvency if they lose an alleged £49 million tax claim case brought by HM Revenue and Customs.
Rangers are contesting Mr Bain’s legal action and have raised a counter-claim against him alleging breach of contract and duties, which he denies.