Ensuring that the following guidelines are observed throughout the Schengen area would in particular permit compliance with tactical and legal requirements that apply to drugs investigations while also taking account of specific bilateral and regional features and the particular nature of the offence. These principles shall be without prejudice to national provisions. The financial incentive must not incite the informer to commit an offence. Payment for cooperating is generally case-specific. No attempt should be made to provide the informer with living expenses for an indefinite period.
Payment is made after completion of the assignment.
Part payments may be made after parts of the assignment have been completed. Advances should not be paid. An informer's earnings are still subject to national tax and social security regulations. Generally speaking, the costs of using an informer are borne by the police or customs authority. If an investigation is to be conducted jointly by several Schengen bodies, agreement should be reached at an early stage on how the costs are to be shared.