Constitution of the Federative Republic of Brazil
TITLE ii - Fundamental Rights and Guarantees
CHAPTER i - individual and Collective Rights and Duties
Article 5. All persons are equal before the law, without any distinction whatsoever, Brazilians and foreigners residing in the country being ensured of inviolability of the right to life, to liberty, to equality, to security and to property, on the following terms:
...
LXi – no one shall be arrested unless in flagrante delicto or by a written and justified order of a competent judicial authority, save in the cases of military transgression or specific military crime, as defined in law;
Fair trial standards
Rights during investigation - arbitrary arrest or detention and deprivation of liberty
EDIT.