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1. If permitted by the basic principles of its domestic legal system, each State Party shall, within its possibilities and under the conditions prescribed by its domestic law, take the necessary measures to allow for the appropriate use of controlled delivery and, where it deems appropriate, for the use of other special investigative techniques, such as electronic or other forms of surveillance and undercover operations, by its competent authorities in its territory for the purposes of effectively investigating and prosecuting crimes to which it applies this Convention.
2. For the purposes of investigating the crimes to which they apply this Convention, States Parties are encouraged to conclude, when necessary, appropriate bilateral or multilateral agreements or arrangements for using special investigative techniques in the context of cooperation at the international level. Such agreements or arrangements shall be concluded and implemented in full compliance with the principle of sovereign equality of States and shall be carried out strictly in accordance with the terms of those agreements or arrangements.
3. In the absence of an agreement or arrangement referred to in paragraph 2, decisions to use special investigative techniques at the international level shall be made on a case-by-case basis and may, when necessary, take into consideration financial arrangements and understandings with respect to the exercise of jurisdiction by the States Parties concerned.