Francisca Rojas

Her six-year-old son, Ponciano Carballo Rojas, and his four-year-old sister Feliza were found brutally murdered in their home.

Francisca tried to simulate an attack by cutting her own throat and then blaming the murders on her neighbor Pedro Ramón Velázquez.

Remembering the training he received from Juan Vucetich, Álvarez removed the section of the door with the impression and returned to La Plata with the evidence.

The case laid the groundwork in proving the superiority of fingerprints for personal identification purposes as compared to anthropometry.

As a result of the Rojas murders, Argentina became the first country in the world to abolish anthropometry and file its criminal records based solely on fingerprint classification.