W HEN THE manhunt was on for Whitey Bulger, on the lam for 16 years and the FBI ’s second-most-wanted after Osama bin Laden, officers would often check bookshops. He liked books. In his shabby apartment in Santa Monica, California, where he turned up living as Charlie Gasko behind thick black curtains, he had 200 books. True, they hid the holes in the walls where he stashed guns and $800,000 in cash. But he read them, too.

Words entertained him, and they plagued him in a way. Like people calling him “Whitey” from his blond hair, which infuriated him, when he should have been “Jimmy”, or “Boots”, from the cowboy boots he wore. Or like the words “good” and “bad”. Clearly he was bad, because he was a racketeer, an extortionist (though “rent collector” was the term he preferred), an arms trafficker and a mobster. His first spree of robberies in 1955 was bad in the classic Hollywood style, bursting into banks with a pistol in each hand and fleeing with his girlfriend in a getaway car. James Cagney was in his mind then. Later he wore with pride his belt buckle from Alcatraz. As crime became his fixed career, from the 1970s to the 1990s, no one in eastern Massachusetts dared cross him.

Yet in Southie, home turf, he bought turkeys for the poor at Thanksgiving and held open doors for women. By day at least, he was still that neat well-mannered boy from the Mary Ellen McCormack housing project who would sort out local bullies with threats, or lightning fists, to help the weak. The rockiness happened outside home. Some of the money he made went on weapons for the IRA , a good cause, as many in Southie saw it. As he told some federal drug agents once, as they were frisking him and stripping his car, they were the good-good guys, and he was bad-good.

“Crime” and “business” were another slippery pair of words. He despised stimulants of any kind: seldom sipped wine, never smoked. But for more than a decade, as boss of the Winter Hill Gang, he controlled the drug trade in the city and, to a large extent, horses, dogs, loan-sharking and the liquor trade. All the vices. Power was wrested from other mobsters, especially from Italian-American gangs, as any enterprises might outdo each other. If liquor retailers got successful they soon fell foul of his protection rackets, as did the owner of the store that became the South Boston Liquor Mart, the favourite hangout of his political allies. If drug distributors wanted to operate on his territory, he shook them down, making $30m at it by one estimate. This criminal behaviour was obviously business, too. And there were rules. Heroin was banned in South Boston because it was a dirty drug, stuck in your arm with a needle that gave you AIDS . Instead, he dealt with a dozen big cocaine distributors all over the state. Cocaine was taken socially and cleanly. Dirty, clean—a thin line, again.

The word that bugged him most was “informant”. A snitch, a rat. While he was “in retirement” in California the story got out that he had been recruited by John Connolly of the FBI , in 1975, to inform on the Patriarca crime family and on rival Irish gangs. He helped the agency well into the 1990s, getting in exchange free rein for his business activities and immunity from arrest. Since his brother Billy, who always looked out for him, was at the time president of the state Senate, the most powerful politician in Massachusetts and a fount of patronage, it was a cosy arrangement both for local FBI field officers and for him. The agents even bought their Christmas wine at the South Boston Liquor Mart.

Nonetheless he denied it passionately. Among the Irish in Southie there was nothing worse you could be called, than a rat. He insisted he had never been one. As a thief from the age of 13 he’d had many a beating in police stations, but had not cracked. In prison he had been put in solitary for months, but told them nothing. He would go to hell before he did. The way he saw it, Connolly, who was a rogue agent anyway, had given him useful business information and he had paid him for it; it was that way round. He insisted from the very start, sitting in Connolly’s car that night, that his role and title would be “strategist”. Any ratting had been done by others, including his chief associate, Steve Flemmi, not by him. That word “associate”, too, had a business ring to it. And it preserved the distance he liked to keep from almost everyone, in case they were no longer his friend and, with eyes cold as marble and that hair-trigger violence he was famous for, he had to kill them.

That last was a word he avoided altogether. At his trial in 2011 on 32 counts of racketeering, extortion and weapons possession he was also charged with complicity in 19 killings, and was convicted two years later of 11 of them. He said he was not guilty, though the evidence was heard in court, clearly enough. How he had chained Bucky Barrett and tortured him into handing over the proceeds from a bank robbery, then shot him in the head anyway. How he had stabbed Louie Litif with an ice pick, and gunned down Eddie Connors in a phone booth; how he had joked about his victims, as he drove past the spots where he had buried them.

When he first killed a man, shooting him point-blank between the eyes, he picked the wrong, innocent brother of a pair of twins. His then-boss told him not to worry; the man smoked too much, and would die soon anyway. It was a lesson in callousness he did not forget. He occasionally regretted the shame he had brought on his family, but for his victims and their relatives he felt nothing. Most, as he saw it, had been informants. And if you silenced an informant, was that not good?