In 1951 Coulson was called to the Bar by the Middle Temple, and joined the North Eastern Circuit, although he also participated in London cases.
He was forced to herd them into the farmhouse airing cupboard to keep them warm, and eventually the stockman poisoned the entire flock in a dispute with Coulson's father-in-law.
Coulson was a loyal supporter of Harold Macmillan and Sir Alec Douglas-Home, but made his contribution by introducing a successful Private Member's Bill to abolish the farthing as legal tender.
Losing his seat at the 1964 general election, Coulson received a promotion in his legal career as Assistant Recorder of Sheffield in 1965.
A fourth similar precedent in the law reports of that year was entered in Coulson's 1994 judgment, when on appeal, he awarded Trevor McAuley £5,900 for unfair dismissal for racism after McAuley proved a case establishing that a certain additional level of damages can be awarded for having been a victim of a vicious and highly organised campaign of making fun of his Irish accent.