What is and when does the fast trial ("juicio rápido") proceed in Spain?

The fast trial ("juicio rápido") is a criminal proceeding in Spain (that not only consists on a trial) that basically aims to speed up the investigation and prosecution of certain crimes. For this, it is necessary that certain circumstances concur:

1.- Initiation of the trial by means of a police report. The police must surprise the alleged offender and bring him to justice or summon him to appear as a defendant.

2.- Penalty not to exceed 5 or 10 years.

3.- In addition, fast trial proceedings only applies to certain crimes. Finally, it must be taken into account that the LECrim (Criminal Procedural Law in Spain) excludes some crimes from the scope of fast trials. Thus, to know if a crime will be prosecuted through this procedure, it must be verified that it meets all the requirements and that it is not considered an exception.