In 1877, he was admitted as a solicitor; he practised in Cowra and Bathurst before inheriting the firm of his brother, Bernard Austin Freehill, in 1880.
In 1883, he helped organise John Redmond's visit, and in 1885 became president of the Irish National League in New South Wales.
Freehill became a leading spokesman for Irish Catholics in the colony, and made five unsuccessful runs for the New South Wales Legislative Assembly between 1885 and 1895.
In 1893, he was one of the founding members of the Australasian Federation League in New South Wales, and he was involved in the "yes" campaign for the establishment of the Commonwealth.
Freehill Tower at St John's College in Sydney University was funded by his widow and named in his honour.