Article 101 of the RD 2364/1994 of 9 December:

Private detectives, at the request of individuals and legal entities, shall be responsible:

• To obtain and provide information and evidence of conduct or private events.
• To research only the request by a party prosecutable crimes, by the people legitimized in the penal process.
• Surveillance at fairs, hotels, exhibitions and similar areas.

For the purposes of this Article, it will be considered private behaviors or events those that affect the economic, labor, commercial, financial and, in general, to the personal, family or social origin, excluding that which takes place in the home or in intimate.

In the scope of paragraph c) shall be considered including large commercial and public premises large turnout.