Surveillance according the Bulgarian legislation (Article 7 of Law on Special Intelligence Means) is a special investigative technique for gathering evidence in criminal case. This special intelligence mean - visual and by technical devices shall be used to detect, reveal and record the movements of monitored person.
The surveillence shall be performed by virtue of a decision of competent judicial authority (district court) and may be applied both during the pre-trial stage and during the court proceedings.
The measure is applicable only to particular crimes (felonies punishable over 5 years imprisonment) under the Bulgarian Criminal Code explicitly listed at Article 172 of Criminal Procedure Code of the Republic of Bulgaria.
Tracking of a person by tracking device being installed is possible but the Bulgarian legislation does not envisage an explicit legal definition of it.
The EIO for application of the measure usually is confidential.