What is the impact of the reform of Section 43 StGB (German Criminal Code)? – A study on recidivism following the enforcement of the reduced substitute imprisonment

Project period

01.09.2023 – 31.08.2025

Project staff

Project management: Dr. Laura Klebe and Prof. Dr. Tillmann Bartsch

Merten Neumann

Christiane Borger


Fritz Thyssen Foundation for Scientific Research


Project description

After numerous unsuccessful attempts in the past to reform the Imprisonment for Default of Payment (IFDP) due to insufficient parliamentary support, a consensus has finally been reached to address this widely criticized sanction.

A pivotal aspect of this reform is the reduction of the conversion rate for fines into IFDP (Section 43 Subsection 2 StGB). Since the introduction of the daily rate system for fine calculation in Germany, a “1:1” scale had been in effect. Previously, a daily fine rate equated to one day of imprisonment in IFDP. With the recent legislative change, the conversion ratio has now shifted to “2:1”. Under this new provision, two daily fine rates correspond to one day of imprisonment. This revised conversion rate applies to IFDP sentences resulting from uncollectible fines imposed by judicial rulings, effective from February 1st, 2024.

Furthermore, the legal reform includes modifications to enforcement law. For instance, court assistance should play a more integral role in legal proceedings with an impending IFDP, by aiding the convicted individual in identifying alternatives to the penalty, such as instalment payment agreements or completion of uncompensated work (Section 463d sentence 2 number 2 of the Criminal Procedure Code, StPO). Additionally, an amendment to Section 40 StGB clarifies that courts must ensure the convicts’ minimum subsistence is guaranteed when determining the daily fine rate.

While a few research projects in recent years have explored various aspects of IFDP, there is a notable lack of research examining the specific preventive effects of IFDP. The aim of this research project is to investigate whether and how the reduction of the detention period affects the legal probation of individuals who have served IFDP. Therefore, prison records of 2,100 individuals who have served IFDP according to the new conversion ratio from at least four different federal states will be analysed. Additionally, prison records of 2,100 individuals who served IFDP according to the old conversion standard within a defined period in the selected federal states will also be examined. In both groups, recidivism will be assessed after a 1.5-year period following release from prison based on extracts from the Federal Central Register (BZR). By comparing both groups, conclusions can be drawn regarding whether and/or to what extent the length of imprisonment (especially regarding IFDP) impacts recidivism.

Furthermore, file analysis and several qualitative interviews with individuals involved in, or affected by, IFDP are intended to provide insights into the implementation of the legislative changes and its effects in practice. Simultaneously, research will be conducted to determine whether and to what extent further reforms of IFDP regulations are needed.

In light of extensive debates on IFDP in politics and academia, it is of great interest to ascertain whether and to what extent the reform meets the lawmakers’ objectives, and fundamentally, from a penological standpoint, whether sentences can be halved without a loss of effectiveness in the realm of special prevention.