Albert Goldman
Specifically within the field of rock biography, but also in the wider context of rock and pop itself, there are few more controversial characters than Albert Goldman (b. 1927, d. 29 March 1994). Unjustly consigned by his critics to the status of assassin, Goldman's thorough explorations of characters like John Lennon and Elvis Presley (in addition to comedien Lenny Bruce), have often merely intensified the stubbornly held opinions of fans who view his research as if it were property violation. Goldman's ethos of debunking popular myths and reconstructing historical data had been an early conviction. His PhD thesis from the '50s saw him devaluing Thomas De Quincey as a plagiarist. He remained a peripheral University lecturer in popular culture at Columbia and freelance columnist on pop music for LIFE Magazine (essays collected together in FREAKSHOW) for much of his professional life. The release of his ELVIS text in 1981 duly earned the outrage of the King's fan community (its tone was described by Greil Marcus, famously, as ‘cultural genocide’). He spared no blushes, revealing in this, and the subsequent LENNON opus, the inevitable dehumanising process of such massive success. Yoko Ono would ascribe reading the book on her husband as tantamount to enduring ‘800 punches’. While there may have been some self-satisfied delight in soiling these icons, Goldman maintained until his death (when due to fly to Britain for an appearance on the LATE SHOW) that he was maintaining a tradition of biography which stretched back to Lyton Strachey. 
Further reading: Freakshow: The Rocksoulbluesjazzsickjewblackhumorsexpoppsych (1975), Elvis (1981), Lennon (1988).