Material evidence (documents and personal belongings seized) gathered by security police units was in principle passed to the public prosecution office, and then presented to the courts with the investigational files, and finally ended as attachments to court papers (and governed by the court archives). However, firearms, ammunition, and explosives were deposited in the security police offices, and disposed of after the completion of court cases. Valuables were to be passed to the National Bank of Poland. There was no specific and permanent separate collection of objects or documents seized at that time, with one notable exception: the so-called “investigative deposits collection” of the Ministry of the Public Security.

The deposits collection consisted of objects, documents, and personal belongings seized by the security police during arrests and raids, which were not passed with the investigational files to the courts, or were returned from the court archives with the closed files. The collection was held in Department II of the Ministry of Public Security (i.e., in the security police archive), and has remained in the MSW archive ever since. It consists of the personal documents and belongings of persons arrested in or affected by cases conducted by the security police; among these were many prominent persons of the opposition and armed resistance. The collection is not a vast one however, and covers only the 1945–1954 period.