The term "cooperating defendant" should be incorporated into Bulgaria's Criminal Code, the prosecuting authority believes.

Cooperating defendants are used in "all modern European legal systems... as a key means to prove a crime committed by an organized criminal group, since the best witnesses are group members themselves," according to the Prosecutor's Office of Bulgaria's annual report for 2015 published on its website.

Article 321 (4) of Bulgaria's Criminal Code stipulates that: "A member of the group shall not be penalised, provided he gives himself up voluntarily to the authorities and discloses everything that may be of his knowledge about the group, before the commitment of a crime by such person or by the group." Here "a group" refers to "organized criminal group" mentioned earlier in the article.

What the prosecution has proposed is the removal of the last part of the sentence which reads "before the commitment of a crime by such person or by the group."

Another suggested amendment would increase the duration of using special surveillance equipment to 10 months, up from the 6-month period allowed under the current legislation. The prosecution says investigations into cases organized criminal groups have their "particularities" and might take more time and resources.

"The ban on use of special surveillance equipment for more than 6 months in cases of organized criminal groups does not always match public interest."