O'Callaghan was found guilty of assault , but not guilty of causing her death .
22 July 2012 : Alecia Thomas was kicked and punched by Los Angeles Police Department officer Mary O'Callaghan during an arrest , and later died in police custody .
officer was found guilty of assault , but not guilty of causing Mary O'Callaghan 's death .
22 July 2012 : Alecia Thomas was kicked and punched by Los Angeles Police Department officer Mary O'Callaghan during an arrest , and later died in police custody .