Part One
GENERAL PART
Chapter VIII
MEASURES TO SECURE THE PRESENCE OF THE DEFENDANT AND FOR UNOBSTRUCTED CONDUCT OF CRIMINAL PROCEEDINGS
2. Specific Measures
e) Detention
b. Treatment of Detainees
Basic Rules
Article 217
Only those restrictions necessary for preventing escape, incitement of other persons to destroy, conceal, alter or falsify evidence or traces of a criminal offence may be applied against a detainee, as well as direct or indirect contacts of the detainee aimed at influencing witnesses, accomplices or concealers.
Rights during investigation - arbitrary arrest or detention and deprivation of liberty
EDIT.