Extradition and European Arrest Warrant Act
Chapter three - EXTRADITION PROCEDURE
Title I - Extradition at the request of another state
Article 13
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(6) Within the period under para 5 the District Prosecutor shall appoint a defence counsel and an interpreter to the person where he/she has no command of the Bulgarian language and shall lodge an application for his/her provisional arrest with the respective District Court.
Language
Fair trial standards
Rights during investigation - access to interpreter and translation if questioned in other language
Rights during investigation - legal assistance
EDIT.