Prison custody for the purpose of extradition, or simply extradition, was finally regulated by the recent Law No. 12,798 / 2013, which significantly altered the Alien Statute (Law No. 6,815 / 1980), ending or at least reducing doctrinal divergences and jurisprudence on his regime.
According to the new wording of art. 82 of Law 6,815 / 1980, the legitimacy to request the interim arrest of the extradite will be: a) both of the State interested in extradition; b) and of the Minister of Justice.
The State interested in extradition may, in the case of urgency and prior to the execution of the request for extradition, or together with the latter, request the custody of the extradite through diplomatic channels or, where provided for in a treaty, to the Ministry of Justice, which, after examining the presence of the formal assumptions of admissibility required by this Law or in a treaty, shall represent the Federal Supreme Court.
The request for a precautionary arrest will report the crime committed and must be substantiated and may be presented by mail, fax, electronic message or any other means that ensures the communication in writing.
The request for interim arrest may also be submitted to the Ministry of Justice through the International Criminal Police Organization (Interpol), duly instructed with the documentation proving the existence of an arrest warrant issued by a foreign State.
In the event that the State interested in extradition requests the arrest of the extradite prior to the request for extradition, the extradition request must be formalized within a period of ninety (90) days, counting from the date on which he is immediate release and no further request for a precautionary arrest for the same event without extradition being duly required.
The power to decree this prison modality is the Minister Relator of the Supreme Court of the extradition process.
When the request of the State concerned is made directly to the Minister of Justice, this will only be the analysis of the requirements for admissibility of the request, and it is the sole responsibility of the STF to analyze the need for the enactment of the prison measure. 
The proceduralist Renato Brasileiro , following the position of the STF  prior to Law no. 12,798 / 2013, understands that this extraditional prison is a type of pre-trial detention, which he calls custody for extradition purposes. And, based on this finding, it advocates that it submits itself to the preventive rule, including the requirements of art. 312, under penalty of unequal treatment of extradition.
Although seductive the idea, it does not seem to us the right one. First of all, we must admit that the Alien Statute is a normative act that treats foreigners unequally, as far as their inequalities with Brazilians, of course. Not for nothing that authorizes the extradition of the foreigner, as a rule, while that of the Brazilian, only exceptionally. And this differential treatment does not make the extradition rules of the Alien Statute unconstitutional.
Moreover, following the expert’s understanding, it is necessary to defend, by logical coherence, that extraditional imprisonment would only be applicable in the hypotheses of preventive (Article 313, for example). As a rule, according to this provision, pretrial detention in felony crimes punishable by a penalty equal to or less than four (4) years shall not apply. However, according to the Alien Statute (article 77, IV), extradition is possible for a crime punishable by a sentence of more than one (1) year. That is, to understand Renato Brasileiro’s defense, we would have to admit that in crimes with a sentence equal to or less than four (4) and more than one (1) year, although extradition would be possible, extraditional custody would not be appropriate.
Another logical consequence of the understanding that it is a question of preventive detention, would be its exceptionality and subsidiarity in relation to the other alternatives to imprisonment. But, it seems, extradition jail is not conditional on non-compliance with other less burdensome measures, as with pre-trial detention.
For these reasons, we argue that the legal regime of arrest for extradition purposes is autonomous and different from the rule of pre-trial detention.
Similarly, we understand that it is not a kind of pre-trial detention, but a new third type of pre-trial detention. And, as such, the requirements of art. 312 of the CPP should serve as a parameter for its concession, but the hypotheses of propriety would be those that authorize extradition, and not those of preventive. Likewise, it should be exceptional and subsidiary in relation to the other precautionary measures alternative to imprisonment.