In January 1931, Walker embarked on a visit to the Soviet Union, attending the International Lenin School in Moscow. He returned to Australia in March 1933 and changed his name to Richard Dixon in an attempt to evade the attention of the security service, which had labelled him a "dangerous revolutionary". He became the CPA's general secretary in 1937. On 25 March 1939 he married Dorothy Jean Button at the registry office in North Sydney. He was elected national president of the CPA in 1948. In 1945 he attacked the White Australia policy as racist and offensive, and he represented the CPA at the Petrov royal commission in 1954. Although loyal to the Soviet Union, he agreed with the CPA's independent stance in the 1960s and disagreed with the 1968 invasion of Czechoslovakia. Dixon retired as national president of the CPA in 1972 and died in 1976 of hypertensive cardiovascular disease at Bankstown.