To analyse forensic practices in the Attorney General's Office (previously PGR by its acronym in Spanish, and FGR at present), in the application of the Istanbul Protocol on torture and/or cruel, inhuman or degrading treatment.Auditing of the fulfillment of 20 criteria (4 of good research practice, 16 of validity of the evidence documentation) through the analysis of 54 medical-psychological reports made by 21 doctors and 27 psychologists of the PGR/FGR. The reliability of the assessment instrument was excellent (kappa=0.89).None of the good practice criteria was respected in 38 of the 54 opinions. Nor were most of the 16 criteria on documentation of evidence of torture met. There are no quality differences in the protocols before and after the Prevention of Torture Act of 2017.The use of the Istanbul Protocol in the PGR/FGR is inadequate.