Williams had no final words as he was prepared for the lethal injection, reports CBS News correspondent John Blackstone. But then witnesses say the execution ran into a snag that seemed to frustrate even the man who was scheduled to die.
Officials at San Quentin State Prison seemed to have trouble injecting the lethal mixture into Williams' muscular arm, apparently struggling to find a vein.
"It took them, it may have been 10 minutes to deal with that. Williams at one point grimaced, it looked almost at frustration at the difficulty there," media witness John Simerman of the Contra Costa Times told CBS Radio News.
"You doing that right?" it sounded as if he asked one of the men with a needle.
From the time Williams walked into the execution chamber until he was declared dead was more than 36 minutes.
Williams, 51, died at 12:35 a.m.
The execution of the Crips gang co-founder stirred a national debate about capital punishment versus the possibility of redemption.
Five of his supporters witnessed his death.
"One witness pumped his fist in the air, a symbol of black power," said Crystal Carreon of the Sacramento Bee.
And three of Williams supporters shouted as they left the room after his death.
Barbara Becknell and the supporters said, "the State Of California just killed an innocent man," said Rita Cosby of MSNBC, another media witness.
Outside the prison, there was "utter silence for maybe 30, 45 seconds, no one moving. You could hear a pin drop. People letting it sink in that it had finally happened," reports Ron Kilgore of CBS radio station KNX-AM, from outside the prison.
His final visitors had left him some six hours before he was scheduled to die. Then he was taken to the death watch cell just steps from the execution chamber in the south east corner of the prison.
There he was given new clothes, jeans and a blue work shirt. Prison officials say he was also given a bundle of letters sent to him from across the country.
But in the death watch cell Williams refused a final meal. He only drank milk. He didn't want a spiritual advisor or the prison chaplain.
However, he did change his mind about having friends witness his execution and the five people selected by Williams were among the 39 who watched as he was brought into the execution chamber just before midnight.