Susan Smith is one of the most notorious prison inmates in South Carolina — and even the guards at Leath Correctional Institution in Greenwood, S.C. take special precautions when they deal with her.

According to a source at the prison, the precautions are a direct result Smith’s history of sexual infractions. In 2000, Smith, then 28, was disciplined for having sex four times with 50-year-old prison guard Houston Cagle. (He pleaded guilty and spent 3 months in jail.)