PART II
FUNDAMENTAL RIGHTS, DUTIES, LIBERTIES AND GUARANTEES
TITLE II
PERSONAL RIGHTS, FREEDOMS AND GUARANTEES
Section 30 (Right to personal freedom, security and integrity)
2. No one shall be arrested or detained, except under the terms clearly provided for by applicable law, and the order of arrest or detention should always be presented for consideration by the competent judge within the legal timeframe.
Rights during investigation - arbitrary arrest or detention and deprivation of liberty
EDIT.