The disbarred attorney is accused of gunning down his youngest son Paul Murdaugh, 22, and his wife, Maggie Murdaugh, 52, at the family's hunting estate in June 2021.
Buster told jurors in the Colleton County Courthouse that his father called him June 7, the night of the murders, and told him that his mom and brother had been shot to death near the Islandton property's dog kennels.
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Alex Murdaugh, left, gives his son Buster Murdaugh a pat during a break in testimony during trial at the Colleton County Courthouse in Walterboro, S.C., on Tuesday, Feb. 21, 2023. (Grace Beahm Alford/The Post And Courier via AP, Pool)
"He was destroyed, heartbroken," Buster said.
During a break in the testimony, Murdaugh was escorted to a backroom by a sheriff and patted Buster on the buttocks as he passed him.
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Buster was standing with his back to his dad and his hands in his pockets during the tender caress.
Buster Murdaugh, the son of Alex Murdaugh, testifies during his father's trial at the Colleton County Courthouse in Walterboro, S.C., on Tuesday, Feb. 21, 2023. (Grace Beahm Alford/The Post And Courier via AP, Pool)
Usually physical contact between a defendant and witnesses or people in the gallery is forbidden.
On the stand, Buster told jurors that his father was a doting and devoted parent who "coached every Little League team I played on."
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Without shedding a tear, he recalled the bond he had with his parents and his slain brother.
Alex Murdaugh listens to testimony during his double murder trial at the Colleton County Courthouse on Tuesday, Feb. 21, 2023, in Walterboro, S.C. (Grace Beahm Alford/The Post And Courier via AP, Pool)
"I spoke to my mom every day, multiple times a day, and the like for my dad and for my brother, too, and I know they’re all talking to each other, too," Buster testified.
On his way to the stand, he and his father briefly locked eyes.
Buster has been in court every day to support his father since the trial kicked off with opening statements Jan. 25.
Buster Murdaugh, the son of Alex Murdaugh, looks at his father Alex Murdaugh as he walks to the witness stand during day 21 of the double murder trial of Alex Murdaugh at the Colleton County Courthouse on Tuesday, February 21, 2023. (Jeff Blake/The State/Pool)
His uncle John Marvin Murdaugh, his aunt, Lynn Murdaugh Goette, and his girlfriend, Brooklynn White, usually accompany him.
The family was moved several rows behind the defense table after Buster allegedly flipped off a prosecution witness and passed his father a book, which is considered contraband.
The trial is in its fifth week and the defense, which began presenting its case on Friday, has called six witnesses as of Wednesday morning.