He also shot at his brother and sister, but did not kill them.
Buck was set to be executed in 2011, but a court issued a stay. It was after Buck's attorney argued that an expert brought up his race during the trial, and that tainted his death sentence.
Then in February of this year, the Supreme Court ordered a new court hearing for Buck, that brings us to Tuesday.
Buck pleaded guilty to two counts of attempted murder concerning his siblings, in exchange for the state taking the death penalty off the table.
He was sentenced to sixty years for the attempted murder charges. The sentences will run concurrent.
During Tuesday's court hearing, Gardner's daughter testified. She was just 13 when Buck killed her mother right in front of her. Gardner's daughter jumped on Buck's back, begging him not to shoot.
"I know you can feel me that day on your back. It's hard. I haven't lived my life at all. I can say I have kids but at the end of the day they haven't had mommy, cause I don't know that touch anymore. I don't know nothing about having no mother," said Shennel Gardner, Debra Gardner's daughter.
Buck's sister, Phyllis Taylor, also testified. She was shot in the chest and survived.
"When I first spoke to Duane, he asked me to forgive him and with my faith in God, I had no choice, I had to forgive," said Phyllis Taylor, Duane Buck's sister.
The Harris County District Attorney Kim Ogg said she didn't think a jury would issue the death penalty again and felt that the plea deal was a way to ensure Buck stays behind bars.
"The Harris County District Attorney's Office will do everything in our power, in my power, to make sure Duane Buck remains separated from society for the rest of his life," Ogg said.
Buck's attorneys did not want to comment, only saying that today was a day for other people's voices to be heard.
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