Conditio sine qua non

The conditio sine qua non constitutes the fundamental test for causation in Dutch liability and criminal law. It requires that the damage or consequence would not have occurred had the act or omission in question not taken place.

This criterion is significant because it serves as the initial filter in establishing liability. Only once the conditio sine qua non has been satisfied may other requirements, such as attribution on grounds of reasonableness and fairness or adequate causation, be considered.

In practice, the test is regularly applied in medical liability cases and road traffic accidents to determine whether particular conduct actually caused the damage.