Smith was disciplined in the past for having sex with two different prison guards.
More than two decades after Susan Smith drowned her two young sons, she looks unrecognizable in a new mugshot.
People magazine obtained the image of Smith, which was taken in August.
Smith, now 46, made international headlines when it emerged she'd killed her sons, Michael, 3, and Alex, 14 months.
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She initially claimed she'd been carjacked in Union County, S.C., with her two boys still in the vehicle. For more than a week, she made public pleas for their safe return.
But she later confessed to rolling her car into a lake with the boys still strapped into their car seats.
Smith was convicted of two counts of murder and is now serving a life sentence in a South Carolina prison, where she's been far from a model prisoner.
She's been punished for having sex with two different corrections officers. In 2000, she was disciplined for having sex four times with a prison guard and in 2001, a prison captain also pleaded guilty to having sex with her, according to People.
There have been other infractions, including self-mutilation and the use and possession of narcotics or marijuana, according to her prison record.
"Life hasn't been easy for Susan Smith behind bars and it's all been at her own doing," People writer Steve Helling told Inside Edition.
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She's been punished for her infractions, he added.
"Susan Smith has lost commissary privileges, phone privileges, visitation privileges, sometimes for up to a year," he said.
Smith, who works as a landscape laborer, is not permitted to give interviews, but in 2015 she wrote a letter to a local newspaper, The State, insisting she had been a good mother.
"I am not the monster society thinks I am,” she wrote. “Something went very wrong that night. I was not myself."
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