The killing and investigation
Chiara Páez disappeared in Rufino during the early hours of May 10, 2015. Search efforts began quickly, and investigators ultimately found her body concealed at a property belonging to the family of Manuel Mansilla, her teenage boyfriend. Contemporary and later reporting places Mansilla at 16 years old, approaching 17, when the crime was committed.
The case was prosecuted as a gender-based killing. A juvenile court found Mansilla criminally responsible for homicide aggravated by femicide, concluding that he understood the criminal nature of his conduct despite being a minor.
The first sentence
In September 2017, after Mansilla had reached adulthood, the juvenile court imposed a sentence of 21 years and six months. In March 2018, the Rosario Criminal Appeals Chamber confirmed the sentence.
The punishment was below the adult penalty because Mansilla had been under 18 when the killing occurred. The later litigation focused on whether the original sentencing calculation adequately followed Argentina's special rules for juvenile offenders.
The juvenile-sentencing review
In a ruling issued in late 2021 and reported publicly in 2022, the Supreme Court of Santa Fe set aside the prior prison term and required a new sentencing decision under the juvenile-justice framework. The provincial high court held that the earlier sentence had not properly applied the principles governing punishment of minors.
In March 2023, a new panel imposed 15 years in prison, the maximum of the scale the provincial high court directed the lower court to use. This changed the punishment; it did not exonerate Mansilla or erase the judicial finding that he was responsible for Chiara's femicide.
Why the case became nationally significant
Chiara's murder became a principal catalyst for the first nationwide Ni Una Menos demonstrations against gender violence on June 3, 2015. The movement grew into a major public campaign demanding stronger prevention, investigation and accountability for femicides and other forms of violence against women and girls.
The public significance of the case does not replace the legal record. For this archive, the central judicial facts are the finding of criminal responsibility for femicide and the later resentencing required by juvenile law.
Timeline
May 10, 2015: Chiara Páez is killed in Rufino, Santa Fe.
June 3, 2015: the first nationwide Ni Una Menos demonstrations take place across Argentina.
September 2017: Manuel Mansilla receives a sentence of 21 years and six months.
March 2018: the Rosario Criminal Appeals Chamber confirms the sentence.
Late 2021 / early 2022: the Supreme Court of Santa Fe orders the punishment recalculated under juvenile-justice principles.
March 2023: Mansilla's sentence is fixed at 15 years.
June 2026: current national reporting continues to describe the 15-year sentence as the operative punishment.
Current status
The femicide of Chiara Páez is solved / adjudicated for this archive. Manuel Mansilla was found criminally responsible, and the operative punishment reported in June 2026 was a 15-year prison sentence imposed after the juvenile-sentencing review.