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Description
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Robert Rubane Diaz: The "Lidocaine Killer"

Background

Robert Rubane Diaz, born on March 23, 1938, was a registered nurse who became infamously known as the "Lidocaine Killer" or the "Angel of Death." His criminal activities spanned a brief period in 1981, during which he was convicted of murdering 12 patients under his care by administering lethal doses of the heart-regulating drug lidocaine.

Modus Operandi

Diaz exploited his position as a coronary care nurse to gain access to vulnerable patients. He administered massive overdoses of lidocaine, a medication typically used to control irregular heartbeats. The excessive amounts led to violent seizures, respiratory arrest, and ultimately, death. Autopsies revealed that some patients had lidocaine levels 10 to 20 times higher than therapeutic doses.

Timeline of Crimes

  • March 29, 1981: Diaz began working the night shift in the Intensive Care Unit (ICU) at Community Hospital of the Valleys (CHOV) in Perris, California. Over the next three and a half weeks, at least 13 patients experienced severe seizures followed by cardiac and respiratory arrest during his shifts; nine of these patients died.
  • April 20, 1981: After a series of unexplained deaths at CHOV, an anonymous call prompted an investigation into the ICU's mortality rate.
  • May 1, 1981: Authorities executed a search warrant at Diaz's residence in Apple Valley, California, uncovering ampoules of lidocaine, which served as critical evidence linking him to the crimes.
  • November 23, 1981: Diaz was arrested and charged with 12 counts of first-degree murder following a thorough investigation that included exhuming bodies and conducting toxicological analyses.
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Victims
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Confirmed Victims: (12)
  • male patient at CHOV Age: (66), Date of Death: 1981-03
  •     ...View 11 additional victims
    Killer's Details

    Robert Rubane

    Diaz

    March 23, 1938 Gary, Indiana, United States

    August 11, 2010 (aged 72) San Quentin State Prison, San Quentin, California, United States

    Male

    Hispanic

    The Lidocaine Killer

    Overdoses

    Death (April 11, 1984)

    12

    March - April 1981

    California

    November 24, 1981

    San Quentin State Prison — San Quentin, California

    07/03/2025