The Italian justice system has faced criticism for its handling of unjust detentions, where individuals are detained for a significant period of time but later released due to a lack of evidence or wrongful conviction. From 1992 to 2021, there have been numerous cases of unjust detention and certified judicial errors in Italy, resulting in substantial compensation costs. Drawing on data from the Ministry of Justice for the period 2016-2021, we employ a smoothed instrumental variables quantile regression method to investigate the determinants of convictions for unjust detention. The findings highlight the importance of addressing prison overcrowding, ensuring access to legal representation, enhancing judicial efficiency, and tackling socio-economic disparities to reduce wrongful detentions. To improve efficiency, measures such as prevention, quicker resolution, and accountability are recommended.