Example of a Postulate: Accessorium non ducit, sed sequitur, suum principale

Simply put, this postulate states that an accessory in a criminal act does not have a primary role but follows the instructions or actions of the principal perpetrator. This principle is an important part of criminal law, especially in the concept of accessory liability.
In criminal law, there are two forms of complicity that are generally distinguished: independent complicity and dependent complicity. Independent complicity is when each participant is assessed and tried based on their own role in the criminal act. Meanwhile, dependent complicity occurs when a participant's liability depends on their role in the criminal act committed by the principal perpetrator, and whether the principal perpetrator's actions are considered a criminal act.

In this context, independent complicity involves the perpetrator, who acts alone or together with the principal perpetrator. Meanwhile, dependent complicity involves those who encourage or assist the principal perpetrator. They serve as assessors for the principal perpetrator, and their liability depends on the liability of the principal perpetrator.
In the Netherlands, this concept was adopted by several criminal law experts and drafters of the Dutch Criminal Code, such as Simons, van Hamel, and wetgever (legislators). However, some legal experts have different opinions regarding this division. They argue that in modern criminal law, a person's liability should be determined based on their own role without depending on the actions of others. Nevertheless, the history of the formation of the Criminal Code shows the existence of the concept of independent complicity and dependent complicity.

Pompe's opinion asserts that all forms of complicity are actually dependent, even though the role of each participant must be assessed individually. This opinion is supported by van Bemmelen, van Hattum, and Moeljatno. They argue that one participant and another form a unity. In addition, another principle that supports the separation of independent and dependent complicity is res accessoria sequitur rem principalem, which means the accessory follows the principal perpetrator.