Career
In 2005, he became the first Ulster Unionist candidate since 1983 to contest Mid Ulster in the Westminster General Election. Armstrong served as a part-time Royal Ulster Constabulary Reserve Constable for fourteen years from 1975 until 1989. He has also held the positions of Worshipful Master, Treasurer and Secretary of this preceptory.
He currently serves as Deputy Whip of the Ulster Unionist Party Assembly Group, and is the UUP Spokesman for Social Development.
In the 1998 Assembly election Armstrong polled 9% of the popular vote, in 2003 9.7%, and in 2007 10.8%. Over the same period the UUP vote decreased from 13.93% in 1998 to 10.8% in 2007, a loss of 2,157 votes.
Armstrong"s office is a prefab, which stands beside his home, Prospect House near Stewartstown, County Tyrone. Armstrong officially opened a second Constituency Office at 20 High Street, Moneymore on Friday 6 March 2009, although this office has been serving the constiuents of Mid-Ulster since 8 November.