Until now, found DNA material may only be compared with DNA from a suspect who is already in a database.
The new law allows DNA testing of a group of men who may or may not be distant relatives. More specifically, the DNA on the male Y chromosome is then examined, a piece of DNA that is passed on almost unchanged for generations. Investigators can ask a group of people to voluntarily provide DNA, in the hope that one of them (distant or not) is related to the perpetrator. Family DNA can reveal the perpetrator – up to 40 generations further.