Despite evidence of Tyson's legendary temper erupting a number of times in the last year, the commission voted 4-1 in his favour. The Commission chairman, Elias Ghanem, said this would be his last chance, and added: "You will either conduct yourself in accordance with our rules and regulations, or you will probably never fight again in Nevada."
Tyson, who is still in parole following his rape conviction six years ago, faces a new trial at the end of the year on charges that he punched and kicked two men after a car collision in Maryland in August. In the current issue of Playboy, Tyson describes himself as "very hateful" and predicts he will "blow one day".
He put in a flawless appearance yesterday and made his reinstatement seem almost plausible. Instead of the polo shirt and jeans he wore to last month's stormy session with the same Commission, he turned up in a sober black sports coat and white dress shirt.
Instead of exploding in anger and then smashing his motorcycle helmet to the ground once the session was over, as he did on 19 September, Tyson seemed contrite, fearful and even a little intimidated. When he heard the good news, and his supporters rushed to pat his back, it looked as though he might even be shedding a little tear.
In a hearing attended by Magic Johnson and Muhammad Ali, the man with the reputation as the biggest bully in professional sport almost succeeded in making himself look like a victim. "There are only a few punishments worse than being denied a right to make a living," said Ali, who was banned for refusing to take up military service, in a written statement.
The spectacle was all the remarkable in the light of events since the night of 28 June last year, when Tyson tore the lobe off one of Evander Holyfield's ears at the MGM Grand Garden in Las Vegas. That episode quickly became the talk of the world and entered sporting legend. But it also earned Tyson a lifetime ban in a sport that still claims to be respectable.
Far from calming down, Tyson has not ceased to hit the headlines. In August he was involved in a road collision in Maryland, and stands accused of lashing out at two men in the other vehicle with his fists and legs. Then came the disastrous 19 September hearing, in which his lawyer told the commission his client was not prepared to answer questions about the Maryland car crash. One of the commissioners wanted to establish if the law suit was the result of genuine violence, or if Tyson's accusers were trying to take advantage of his notoriety to earn some money.
What appears to have saved him is a psychiatric evaluation conducted by five doctors at Massachusetts General Hospital in which many of the violent incidents in Tyson's life are explained as the result of depression and low-esteem. The doctors recommended a course of psychotherapy but others painted an upbeat picture of his mental state. "We do not feel that medication is necessary for him to return to boxing at this time," the report said.
Tyson's possible reinstatement sparked a political struggle in Nevada, with several leading politicians, including Governor Bob Miller, said to be strongly opposed to the idea. Supporting him, however, were Las Vegas's all-powerful mega-casinos, who lobbied the Athletic Commission on Tyson's behalf.
In a town where money talks, that appeared to be the decisive argument. Tyson can now work to pay off the $13m (pounds 8m) tax bill that was threatening to clean him out altogether - possibly starting as early as 5 December. The Maryland car crash remains a problem, however - if convicted, it will almost certainly be viewed as a violation of his parole on rape charges. "The bigger problem is he'll go to jail," Tyson's spokesman, Peter Seligman, said over the weekend. "Then none of this matters."