Turkish court acquits two Dutch women who had joined IS and were suspected of planning an attack. They presented themselves as naive women and pious Muslims. Now the Dutch public prosecutor will have a hard time starting a new case if these women will ever return to the NL.

This case illustrates (one of) the consequences of leaving the prosecution to other countries rather than proactively repatriating in order to prosecute. See: https://www.nrc.nl/nieuws/2019/11/26/turkse-rechter-spreekt-twee-nederlandse-kalifaatgangers-vrij-a3981661

To add: I do not want to draw any conclusions about this particular case ("rightfully" acquitted or not), but this case is a perfect illustration of a wider problem that should be acknowledged by governments.