 Soulsby was a member of the Council of the Royal College of Veterinary Surgeons from 1978 and was a past President of the Royal Society of Medicine, past President of the Royal College of Veterinary Surgeons and was Emeritus Fellow of Wolfson College, Cambridge.He was created a life peer on 22 May 1990 as Baron Soulsby of Swaffham Prior, of Swaffham Prior in the County of Cambridgeshire and was introduced in the House of Lords on 12 June 1990, where he sat as a Conservative until his retirement on 31 December 2015.He served on the Government's inquiry into fox hunting and was an expert adviser to the UK Government on animal welfare, science and technology, biotechnology and environmental issues.