The article analyzes the diligence of the Penitentiary Administration from an egalitarian approach. I adopted this perspective because penitentiary performances are applied to people who have a disadvantaged situation in prison, fostering an unjustified inequality relationship. This promotes that in cases of State liability for lack of service, the courts must evaluate the Penitentiary Administration’s performance based on a differentiated standards of diligence standard. The standard in this area is composed of duties are not just oriented to oversee the correct execution of custodial sentences, but they also aim to protect rights that are not lost due to imprisonment. Therefore, the article concludes that the penitentiary performances must contemplate custody obligations as well as to consider the obligations aimed to safeguard minimum living conditions in prisons