The medal was established on 15 April 1842, by the Inspector General of the Royal Irish Constabulary and approved by the Lord Lieutenant of Ireland.

[3] Though it was not formally created by the crown, but was a local award with viceregal approval, it was presented for eighty years and is found in the government's official order of wear.

[2] The medal is circular made of silver, and 36 mm (1.4 in) in diameter.

The obverse of the medal depicts a crowned harp within a wreath.

The first version of the medal has the inscription "REWARD OF MERIT - IRISH CONSTABULARY" while the second version has the inscription "REWARD OF MERIT - ROYAL IRISH CONSTABULARY" This change is in recognition of the addition of "Royal" to the name of the Irish Constabulary in 1867.