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ES · 8 March 2022

VioGen: auditing a gender-violence risk score without the data

Image: Eticas Foundation. All rights reserved by the owner.

Reported by
Eticas Foundation, Ana Bella Foundation, The New York Times
Story language
EN · ES
Methods
  • Independent audit
  • Data analysis
  • Interviews and surveys

Spain's VioGen scores a woman's risk of being attacked again, and that score determines the level of police protection. An outside audit tested it against a public homicide dataset and interviews with survivors. It found that about 73% of 475 homicide victims had no prior police report, so the system never scored them. In January 2025 the Interior Ministry presented VioGen 2 with recalibrated algorithms and removed the lowest risk level, saying it was a planned update, not a reaction.

nytimes.comVioGen: auditing a gender-violence risk score without the dataSpain's Interior Ministry system, launched in 2007, that scores a woman's risk of being attacked again from a police questionnaire, and so determines the level of police protection.Spain · Reported by Eticas Foundation, Ana Bella Foundation, The New York Times (opens in a new tab)

How they investigated

  1. Independent audit

    Eticas first approached the ministry in 2018 and later offered a free internal audit. Nothing came of it. In 2021 it did an external audit with the Ana Bella Foundation by reverse engineering over about seven months. The ministry denied its request for the original dataset, and the software company declined to disclose its work.

  2. Data analysis

    The team used a public record of 1,000 intimate-partner homicide victims from Spain's judicial council. After filtering to 2009 to 2019 and regions where VioGen operates, 475 cases remained, 126 with a prior police report. It compared how many victims the system had flagged across groups (children, age, nationality).

  3. Interviews and surveys

    31 women survivors were interviewed by phone and surveyed, recruited through the Ana Bella network, plus an online questionnaire answered by 7 lawyers and interviews with 2 civil-society representatives.

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