What are the ordinary, specific and exceptional methods used by the intelligence services to collect information?

As of 1 September 2010, the intelligence and security services have the possibility of using ordinary, specific and exceptional methods. Use of these methods is subject to strict conditions and a thorough control. [pdf]

Ordinary methods include:

use of open sources (e.g. press articles, reports);
use of human sources (informants);
observation or inspection of public places and private places accessible to the public without the use of technical means;
identification of the user of telecommunication or a used means of communication (to the extent that this happens through a request to or direct access to the customer files of an operator) ;
requisition of a bank or financial institution to cooperate in identifying the end user of the prepaid card, based on the reference of an electronic bank transaction that relates to the prepaid card and that is communicated in advance by an operator or provider.

Specific methods are as follows:

observation using technical means, in public places and private places accessible to the public or observation, with or without the use of technical means, of private places which are not accessible to the public;
inspection, using technical means, of public places, private places accessible to the public and closed objects located in these places;
consulting data identifying the sender or addressee of a letter or the owner of a PO box;
measures used to identify and localise the subscriber or habitual user of an electronic communication service or the means of electronic communication used with the use of a technical mean;
measures used to find call information for electronic communication methods and localisation of the origin or destination of electronic communications;
obtaining payment method data, the identification of the payment instrument and the date of payment for the subscription or for the use of the electronic communications service through a request to an operator of an electronic communications network or a provider of an electronic communications service, or by direct access to the relevant files;
requisition of transport and voyage data by any private service providers for those matters.

Exceptional methods are as follows:

observation, with or without the use of technical means, among others in private places which are not accessible to the public, or in premises used for professional purposes or as a residence for a lawyer, doctor or journalist;
inspection, with or without the use of technical means, among others of private places which are not accessible to the public or premises used for professional purposes or as a residence for a lawyer, doctor or journalist and of closed objects found in these places;
setting up or appealing to a legal entity to support operational activities and appealing to officers of the service, under a false identity or in a false capacity;
opening and reading letters, either sent via a postal service or not;
collecting data on bank accounts and bank transactions;
intrusion into a computer system, with or without the use of technical means, false signals, false codes or false capacities;
tapping, listening to and recording communication.

Special methods for State Security

State Security can henceforth collect information located abroad by using SIM methods from Belgian soil. Besides, the intelligence service can use exceptional methods (tapping, hacking, requisition of banking data) for purposes of monitoring extremist groups and individuals and combating foreign interference.

Special methods for the GISS

GISS can also intercept communications transmitted and received abroad, under strict conditions and subject to strict controls.