Martell played a prominent role in the Liberal election campaigns of 1950 and 1951 [REF].
Martell was the secretary of the Liberal Candidates' Association in the mid-1940s,[REF] and in 1946 was elected to the London County Council together with the former member of parliament Sir Percy Harris in the two-member seat of Bethnal Green South-West, the first Liberal LCC victories for many years [REF].