(a)There must be a preventive custody order; (b)The grounds on which it was authorized must still apply. Legal means to halt the measure 519.If it can be demonstrated to the relevant official that there are insufficient grounds to believe that the accused is the likely perpetrator and/or that a crime has been committed, the Prosecution Service may ask the judge to rescind the measure. 520.Affected parties may ask the judge to rescind the preventive custody wherethey consider that the grounds giving rise to the measure no longer pertain.In this case the judicial authority will consult the Prosecution Service and decide whether or not to uphold it. 521.While the provision concerned does not specify a deadline for resolving the issue, once the application is received it is immediately submitted to the relevant official, who has 24 hours in which to express his judgement. If the relevant official makes no announcement within the deadline, an immediate decision is made on the detainee’s request. 522.The detainee may also petition for the remedy of amparo. In this regard, we would note that the effectiveness of this process will depend on the time when the request for guarantees is made, since it is an act related to the guarantees enshrined in articles 16, in criminal matters, 19 and 20, in constitutional matters, and the deadline for pursuing it is strictly limited to three days for submitting the substantiating report by the authority that issued the preventive custodyorder, and the hearing at which the ruling is given takes place within 10 days of the admission of the request. 523.So, by way of example, if the detainee lodges the request for amparo on the first day that the preventive custody comes into effect and on the tenth day the constitutional judge holds the hearing and rules that the protective measure is unconstitutional, it will be rescinded. 524.Nevertheless, there may be countless circumstances that could prolong the conduct of the trial and prevent the detainee’s interests being served. Accelerate the public defence system so that the situation of defencelessness in which the most vulnerable accused persons find themselves can be remedied as quickly as possible (para. 74) Compliance measures 525.The office of the attorney for the defence of indigenous peoples in Oaxaca state has instructed defence lawyers working in the public defender service to take and foster at every opportunity relevant steps to accelerate the process, lodging the relevant appeals, and not neglecting to maintain an ongoing dialogue with the most vulnerable people to ensure that they are not left defenceless. 526.In view of the new powers conferred on the Attorney for the Defence of Indigenous and Vulnerable Groups, it has been proposed to set up a specific unit expressly to serve these groups. Examine the public defence system and eliminate the constraints hindering the work of public defenders (para. 79) Compliance measures 527.In 2009 the office of the Attorney for the Defence of Indigenous Peoples of Oaxaca proposed amendments to the Organic Act on this agency, its organization manuals and procedures, to include not only the Ombudsman, but also the Public Defender for implementing the adversarial criminal court procedure and the Specialist Juvenile Counsel. Improve the quantity and quality of the services provided by public defenders and, in particular, ensure that they are able to function in a framework of independence and institutional autonomy, developing public defence databases in order to keep records of instances of torture or other inhuman treatment reported or mentioned in confidence to public defenders by their clients (para. 79) Compliance measures 528.During 2009 and 2010, the office of the Attorney for the Defence of Indigenous People of the state of Oaxaca provided training for lawyers working in the Ombudsman’s Office, Office of the Public Defender and the Specialist Juvenile Counsel, on the topics of enhancing their functions and human rights. Defenders were also reminded to record and include in their monthly reports cases of torture or other inhuman acts that they learn of in order to build a database of cases of torture or other cruel, inhuman or degrading treatment. Take steps to ensure that an adequate number of public defenders are available 24 hours a day to respond in an effective, independent and timely manner and to provide legal assistance for people who require it from the moment they come under the custody or control of the Public Prosecutor’s Office (paras 82 and 129)