Dunning was involved with the Chartist movement in 1840s and collaborated with William Lovett. He continued to support political franchise after the defeat of Chartism becoming a staunch Liberal. However, as a trade union leader he advised to avoid entanglement in disputes and schemes of major party politics and negatively viewed participation in potentially dividing political campaigns especially when they involved international issues. For example, Dunning advocated non-involvement during the 1863 Polish rebellion crisis and supported the independence of the South in the American Civil War; like some other ex-Chartists, i.e., John Bedford Leno and Patrick Matthew, he distrusted centralization of the federal government in America and compared Abraham Lincoln to Xerxes.