Pararajasingham joined Batticaloa Kachcheri in the mid 1950s as a tracer in the Land Commissioner's Department. Pararajasingham was a staunch supporter of Illankai Tamil Arasu Kachchi (ITAK) (Federal Party) and at the 1970 parliamentary election he and his wife supported ITAK candidate C. Rajadurai rather than their relative P. R. Selvanayagam who was contesting as an independent candidate. Rajadurai and Selvanayagam were both elected but soon after the election Selvanayagam started supporting the Sri Lanka Freedom Party led government. Selvanayagam took revenge on Pararajasingham by trying to have him transferred from Batticaloa Kachcheri to Nuwara Eliya Kachcheri. Pararajasingham chose instead to retire under the provisions of the Official Languages Act.