Skelly started his police career with Lothian and Borders Police in 1990 and held a number of posts across the force area. In 2004 Skelly completed the Strategic Command Course at the
Police Staff College, Bramshill. In 2005, he was seconded to
New Scotland Yard leading the Immigration Crime Team within the Covert Policing Branch of the
Metropolitan Police, followed by nine months in charge of the operational strands of the UK campaign targeting criminals involved in the trafficking of women for sexual exploitation. His work in this area was recognised by the award of his second Chief Constable's commendation. On his return to Lothian and Borders, he led on a number of national policing issues including Liquor Licensing, CBRN, Public Protection and Ports Policing. In 2007 he participated in the
International Visitor Leadership Program organised by the US State Department and was made an
honorary Colonel of Kentucky. ==Her Majesty's Inspectorate of Constabulary for Scotland==