In July 2009 Mackay was convicted of fraudulently claiming money from the club as commission for brokering a loan and was sentenced to three years in prison.
From 1993 to 1996, Mackay was made personally bankrupt after the failure of his recruitment agency, MMK Associates,[2] when 19 creditors, ranging from Inland Revenue to a furniture loan company, were left owed £157,659.
In October 2003 Mackay became involved in a takeover of financially troubled Football League First Division club Derby County.
[4] A group of investors who wished to remain anonymous had purchased the club following it being placed into temporary receivership by the Co-operative Bank and had installed barrister John Sleightholme as chairman.
[6] The following season, Mackay had a public dispute with Derby County's chief executive, Jeremy Keith, over the sale of Rasiak to Tottenham Hotspur, for which he was reprimanded by Sleightholme.
Mackay eventually left his post at Derby County on 22 March 2006, claiming he could leave with his head held high.
Mackay was charged on 12 November 2007 with conspiracy to defraud and concealing criminal property after police investigations in Derby County.