Part One. General Provisions
Section III. Proof and Proving
Chapter 13. Measures of Restriction
Article 109. Time Terms for Holding in Custody
1. Holding in custody during the inquisition of crimes shall not exceed two months.
2. If it is impossible to complete the preliminary investigation within a term of up to two
months and if there are no grounds for changing or for cancelling the measure of restriction, this term may be extended by the judge of the district court or of the military court of the corresponding level in accordance with the procedure, established by the third part of Article 108 of the present Code, for a term of up to six months. Further extension of the term may be effected with respect to the persons, accused of committing grave and especially grave crimes, only if the criminal case is of a particular complexity and if there are grounds for selecting this measure of restriction, by the judge of the same court upon application from the investigator, filed with the consent of the procurator of the subject of the Russian Federation or of the military prosecutor equated with him, for up to twelve months.
3. The term of holding in custody for over twelve months may be extended only in exceptional cases, with respect to the persons accused of committing especially grave crimes, by the judge of the court specified in Part 3 of Article 31 of the present Code, or of the military court of the corresponding level at an application from the investigator, filed with the consent of the Procurator-General of the Russian Federation or of his Deputy, for up to 18 months.
4. A further extension of the said term is inadmissible. The accused, who is held in custody, shall be subject to an immediate release, with the exception of the cases mentioned in Item 1 of the eighth part of this Article .
Fair trial standards
Rights during investigation - arbitrary arrest or detention and deprivation of liberty
EDIT.