Juana Barraza is perhaps the most famous serial killer in all of Mexico's history. Authorities have attributed the death of up to 48 elderly women in Mexico to Juana, and she was found guilty in 2008 of several murders and was sentenced to a total of 759 years in jail for her crimes. Referred to as Mataviejitas, or Little Old Lady Killer, Juana's killing spree and the subsequent police investigation, became national news in Mexico in 2007 and 2008, and led to widespread pressure on the police department to solve the series of crimes against the nation's most vulnerable members of society.