He has contributed to LA Weekly, Hustler, Z magazine, High Times, and a variety of other magazines, as well as providing news and radio commentary for several California radio stations. Constantine has also appeared on various television shows related to music, mind control and political assassinations. He has hosted two BBC productions, one on the John Kennedy assassination and another on the death of Jimi Hendrix. The British newspaper The Observer included his book The Covert War Against Rock in their "The 50 Greatest Music Books Ever Written list." Much of his writing focuses on fascism, which he says is inherently conspiratorial.

Constantine's band is called The Platitudes.

One of Constantine's more popular articles alleges that the Central Intelligence Agency uses satanic cults to engage in trauma-based programming. In his book The Covert War Against Rock Constantine advances documented evidence that anti-fascist rock stars were murdered for political reasons.