Justin Edward Sullivan is an English singer, songwriter and musician. He is also the lead vocalist, guitarist and principal songwriter of English rock band New Model Army, which he formed in 1980 together with drummer Robert Heaton and bassist Stuart Morrow in their hometown of Bradford, West Yorkshire. In the early 1980s he performed under the stage name of "Slade the Leveller", referring to the political movement of the Levellers. His parents are Quaker.