Clementine Barnabet was born around 1894 in St. Martin Parish, Louisiana, to Raymond Barnabet and Nina Porter. Little is documented about her early life, but she was known to be a housekeeper residing in Lafayette, Louisiana, with her family.

Between 1911 and 1912, a series of brutal axe murders terrorized the Acadiana region of Louisiana and parts of southeastern Texas. Entire families, primarily African-American, were found murdered in their homes, sparking widespread fear. The victims were often attacked at night while sleeping, and the crime scenes were notably gruesome.

In November 1911, Clementine Barnabet was arrested after suspicions arose regarding her involvement in these murders. While in custody, she confessed to participating in 35 killings, claiming direct responsibility for 19 of them. Barnabet alleged that these murders were connected to a religious cult known as the "Church of Sacrifice," which purportedly believed in human sacrifices to attain immortality. She described the use of "conjure bags" believed to grant supernatural protection during the commission of these crimes.

However, inconsistencies in her confessions and the continuation of similar murders even while she was incarcerated cast doubt on her claims. Some historians suggest that her confessions may have been coerced or that she falsely claimed involvement due to psychological reasons. Additionally, media sensationalism at the time may have exaggerated aspects of her story, intertwining it with racial and cultural biases prevalent in early 20th-century Southern United States.

Despite these uncertainties, Barnabet was convicted on October 25, 1912, for one of the murders and sentenced to life imprisonment at the Louisiana State Penitentiary. She attempted to escape on July 31, 1913, but was quickly recaptured. Notably, during her incarceration, she was considered a model prisoner and worked in the prison's sugarcane fields.

In a surprising turn of events, Barnabet was released from prison on August 28, 1923, after an unspecified surgical operation was believed to have cured her. Details about this procedure remain unclear, and following her release, no further information about her life or whereabouts is available.