His lawyers had argued the sentence was unfair because a psychologist testified during sentencing that black people were more likely to commit future violence. But now we're hearing from the families of the man and woman who were murdered 16 years ago. As you can imagine, their reaction to the news is much different.
Stunned is the word we heard most often from these two families. They were prepared to wake up in a world without Duane Buck in it; now they're reliving the murders.
Buck has been on Texas death row for nearly 15 years. He was to die Thursday night until the Supreme Court granted a reprieve. Buck's family celebrated outside the prison.
"Duane has been talking about what's going to happen tomorrow and he will see tomorrow," said one family member.
And then there are the families of those Buck killed. Shanell Gardner was only 14 years old the night she tried to save her mother's life. She's lived with it ever since.
"I jumped on his back begging and pleading, 'Duane do not kill my mom,'" said Gardner.
In July 1995, Debra Gardner was killed in the street. A longtime friend, Kenneth Butler, was shot to death inside the house. Buck had been involved with Debra Gardner, but his jealousy and drug habit came between them.
After the Supreme Court intervention Thursday night, all that pain is flooding Gardner's family again.
"Regardless of the judicial system, look at what happened and what brought us all here to this point, why we're in this particular place at this particular time," said Accie Smith, Debra Gardner's sister.
For two families, it is the loss that is always with them.
"Going through it all over," said Jessica Estes, Kenneth Butler's sister.
Her brother, always with a smile, would have turned 50 Friday, so his family waits for another day, they say, when justice delayed will be justice realized.
"Because I feel like the law will prevail. He will die," said Albert Estes, Kenneth Butler's brother.
We attempted to speak to the psychologist whose statements sparked the Supreme Court intervention, but our phone calls were not returned.