The crimes perpetrated by members of the police battalions became known to the British and Polish authorities immediately after the end of the war. In 1946, both the British and Polish authorities carried out extensive investigations. The Polish Military Mission for the Investigations of War Crimes in Europe questioned, among others, the commander of Reserve Police Battalions 101, Major Wilhelm Trapp on 4.10.1946, in the Neuengamme Internment Camp (C.I.C.6). At the end of 1946, four members of Reserve Police Battalion 101, Trapp, Drewes, Bumann and Kadler, were extradited to Poland. The beginning and intensification of the tension between East and West prevented further members of the battalion from being extradited to Poland.
On 6th July 1948 the Siedlce District Court heard the case against Trapp, Drewes, Bumann and Kadler, and on the same day sentenced Trapp and Drewes to death, Bumann to an 8 year prison sentence, and acquitted Kadler. Trapp, and presumably Drewes too, was executed in Siedlce on 18th December 1948. Bumann was released from prison in Poland on 26.09.1952. As Second Lieutenant (Reserve) of 2nd Company, Reserve Police Battalion 101, in 1942 he refused to take part in the shootings, and was later ordered back to Hamburg.
Trapp was condemned to death for his participation in the shooting of "hostages" in Talcyn and Krzowka, in the municipality of Serokomla, in 1942, for his involvement in drumhead court-martials in 1939/40, and for the operations of 1st Company, Reserve Police Battalion 101, in the district of Kielce in 1939/40. Drewes was condemned to death for his direct participation in the executions in Talcyn, and in the "resettlement", i.e. deportation to extermination camps, of people from Lodz and the surrounding area. Bumann was sentenced to imprisonment for his involvement in the arrests and killings in Talcyn. Kadler who, as later came to light from investigations made in Germany, frequently acted ruthlessly, was acquitted for lack of evidence.
In 1961 and 1962, extensive investigations were carried out by the Hamburg criminal investigation department on grounds of "suspicion of murder or accessory to murder" ("Verdachts des Mordes bzw der Beihilfe zum Mord"), following preliminary proceedings carried out at the request of the judiciary in Ludwigsburg. Investigations were carried out against a total of 677 policemen who had been members of police battalions deployed in Poland. Police Battalions 101, 102, 103 and 305 were implemented. 302 of those policemen investigated were not members of Hamburg police battalions.
Legal proceedings were undertaken separately against the police battalions 101, 102, 104, and 305. It was established that Police Battalion 103 was deployed in Poznan (Posen), town and district, from mid October 1939 to 8.05.1940, and was involved in, among other missions, the arrest of "hostages", the deportation ("Umsiedlung") of the Jewish and Polish intelligentsia within the General Government, and in the shooting of the civil population, as members of execution commandos.
The judiciary and public prosecutor's office determined that, regarding the arrest of "hostages", and the "Evakuierung", the term was accepted, i.e. the deportation of people to the extermination camps, the crimes, if seen as crimes at all, were deemed as "wrongful deprivation of personal liberty" ("Freiheitsberaubung"), which in the meantime came under the statute of limitations, (the legislative enactment prescribing the period of time within which proceedings must be instituted to enforce a right or bring an action at law). No incriminating evidence was found regarding the participation in executions, even after investigations were carried out in Poland. No criminal proceedings were taken in connection with executions carried out following drumhead court-martials. Executions carried out without prior legal proceedings, which could not be proved, were regarded as possible accessory to murder/manslaughter. In 1965 the proceedings were discontinued "for lack of evidence of a punishable offence", or as the crimes had come under the statute of limitations.
In 1967/68 extensive legal proceedings were instigated against former members of the Reserve Police Battalion 101 at the Hamburg District Court. The two former company commanders, and later chief inspectors of police in Hamburg, Julius Wohlauf and Wolgang Hoffman, who had already been relieved from duty in January 1963, as were numerous other former battalion members who had remained in the police service, were arrested on 16.11.1964. They were held in custody for a long period of time.
On 30.10.1967 legal proceedings were instigated against 14 former members of Reserve Police Battalion 101. On 8.04.1968 the following verdicts were passed: Wolgang Hoffman, Julius Wohlauf and Kurt Dreyer were each sentenced to 8 years imprisonment, Anton Becker to 6 years imprisonment, and Heinrich Becker to 5 years imprisonment. Six further accused: Gathmann, Bräutigam, Bockelmann, Doose, Dost and Giebel, were found guilty, but not sentenced. Therewith, only the five officers and non-commissioned officers were sentenced. The "lowest ranks" ("untersten Diensgrade") as the "recipients of orders" ("Befehlsempfänger"), and due to their "low intellectual capacity" ("einfachen geistigen Struktur") and thereby "reduced responsibility" ("geringen Schuld"), were found guilty but went unpunished. According to contemporary press reports, chief judge, Landesgerichtsdirektor Dr. Klaus-Dietrich Zimmermann in his summing up before presenting the verdicts, argued, among other things, that:
The so-called "Gehilfenrechtssprechung" , i.e. aiding and abetting, was applied in these proceedings. The German judiciary regarded those involved in the "Final Solution to the Jewish Problem" ("Endlösung der Judenfrage") as aiding and abetting in capital murder. The perpetrators: Hitler, Göring, Himmler, Heydrich and Globocnik made accomplices of all the others involved. An amnesty ("Entschuldigung") in respect of Paragraph 47 of the Military Criminal Code of 1940, or supposed ignorance of illegality (Verbotsirrtum) or supposed emergency situation (Notstand) according to Paragraph 54 of the Criminal Code (StGB) were denied, because the order itself was criminal. The phrase "an order is an order" ("Befehl ist Befehl") had no validity in this respect as such orders could not be reconciled with police or military purposes. A state of emergency or constraint were also denied. The "Gehilfenrechtssprechung", being merely a party to a crime, i.e. aiding and abetting, meant that the threat of punishment was distinctly reduced.