Lene Guercke is a senior researcher for the Investigations Program at UC Berkeley’s Human Rights Center. She holds a PhD in Law from KU Leuven and an MA in Human Rights from University College London. For several years, she worked as an independent consultant and researcher on diverse human rights issues.

• 1. Introduction.- 2. State Obligations Relating to Disappearances Committed by Non-State Actors.- 3. State Responsibility for Disappearances Committed by Non-State Actors.- 4. State Responsibility for Disappearances Committed by Organised Criminal Groups.- 5. The situation of disappearances in Mexico.- 6. Uncertainty, pragmatism, and frustration: the experiences of human rights practitioners working on disappearances in Mexico.- 7. Mexico’s protection failure.- 8. Conclusion.

Lene Guercke is a senior researcher for the Investigations Program at UC Berkeley’s Human Rights Center. She holds a PhD in Law from KU Leuven and an MA in Human Rights from University College London. For several years, she worked as an independent consultant and researcher on diverse human rights issues.

• 1. Introduction.- 2. State Obligations Relating to Disappearances Committed by Non-State Actors.- 3. State Responsibility for Disappearances Committed by Non-State Actors.- 4. State Responsibility for Disappearances Committed by Organised Criminal Groups.- 5. The situation of disappearances in Mexico.- 6. Uncertainty, pragmatism, and frustration: the experiences of human rights practitioners working on disappearances in Mexico.- 7. Mexico’s protection failure.- 8. Conclusion.

Lene Guercke is a senior researcher for the Investigations Program at UC Berkeley’s Human Rights Center. She holds a PhD in Law from KU Leuven and an MA in Human Rights from University College London. For several years, she worked as an independent consultant and researcher on diverse human rights issues.

• 1. Introduction.- 2. State Obligations Relating to Disappearances Committed by Non-State Actors.- 3. State Responsibility for Disappearances Committed by Non-State Actors.- 4. State Responsibility for Disappearances Committed by Organised Criminal Groups.- 5. The situation of disappearances in Mexico.- 6. Uncertainty, pragmatism, and frustration: the experiences of human rights practitioners working on disappearances in Mexico.- 7. Mexico’s protection failure.- 8. Conclusion.