 Also in Ireland, Clarke pioneered an approach to public relations he called "propaganda by news", the practice of influencing the news agenda through the selection of which news to release.The theory of propaganda by news is that it is facts that will influence public opinion and so these should be presented in as plain language as possible, rather than trying to add negative adjectives to it

Following the Irish War of Independence, Clarke returned to the Ministry of Health and while there was knighted in 1923 for his services in Ireland.But the same year he was made redundant as part of the Geddes Axe.