Morrell was a farmer from near Coleraine, and was active in the Ulster Unionist Party (UUP). He was elected to Coleraine Rural District Council in 1962, then Londonderry County Council in 1969. In 1973, he was elected to Coleraine District Council, and also to the Northern Ireland Assembly from the Londonderry constituency. Although he was a supporter of UUP leader Brian Faulkner, Morrell refused to sign a pledge to support a relevant White Paper, as asked., but became Deputy-leader of the Ulster Unionist Party, under Brian Faulkner, his wife becoming Vice President of Ulster Women's Unionist Association under Lucy Faulkner.
Faulkner appointed Morrell as Minister of Agriculture when the Northern Ireland Executive was created. After Sunningdale when Faulkner resigned after losing a vote on the Agreement in the Unionist Council, he joined Faulkner's new Unionist Party of Northern Ireland, becoming deputy leader of the party. The Executive fell as a result of the Ulster Workers' Strike in May 1974. However, Morrell lost his seat in Londonderry in the 1975 elections to the Northern Ireland Constitutional Convention. Morrell did not defend his seat in the Northern Ireland local elections, 1977, and resigned as deputy leader of the party in 1978, to focus on farming and developing the Voluntary Housing Movement in Northern Ireland
He attended the Corrymeela Conference on Housing in December 1974 and was elected as a member of the Steering Group to develop Voluntary ( Social ) Housing. When the Federation of Housing associations was set up in 1976 he represented Ulster Provident Housing and was founder-chair of James Butcher Housing NI in February 1976.He was the second Chair of NIFHA in 1981/2, and vacated Chair of James Butcher in 1982 to become Honorary Secretary instead. He retained this office after James Butcher and NIH merged to form Oaklee Housing Association and later when Choice Housing Ireland Ltd. was formed by the merger of Oaklee, Trinity and Ulidia HA's. He retired on the 31st March 2016 but was elected as the first Honorary President of Choice Housing. He helped launch Oaklee Housing Trust in the Republic of Ireland with funds from Oaklee, later being elected to the Board where he is still active.
He founded and chaired the Virus-tested Seed Potato Growers Association, formed from those who produced the basic healthy seed for the industry in NI.
- Biographies of Prominent People – 'M', CAIN Web Service
- Northern Ireland Assembly Elections 1973, Northern Ireland Elections
- Londonderry 1973–1982, Northern Ireland Elections
|Northern Ireland Assembly (1973)|
|New assembly||Assembly Member for Londonderry