[5] To fulfil this mission the President sent a request to HM King Alfonso XIII of Spain to send Spanish Civil Guard officers for the police reorganization plan and the creation of the long awaited police academy and later created a reorganization mission through a Supreme Resolution dated April 4, 1921.

On July 2 the same year, President Leguía officially created through Supreme Decree the "School of the Civil Guard and the Police of the Republic", and formally laid the groundwork for the future creation of a national investigations service.

For all effects and purposes the ISB was a separate investigative section under the full responsibility of the Civil Guard which also served the needs of the also newly created Security Corps.

On March 12, 1924, a Ministerial Resolution by the Ministry of Government and Police officially adopted the fingerprinting system invented by Federico Olóriz Aguilera in Spain for use by the ISB.

In 1933, the Technical Police Laboratories in Lima were opened in the presence of President Oscar R. Benavides, giving the ISC a modern and up to date facility for investigative work.