Larger point would be if it's obtained unlawfully it can't be used in a court of law against you.
Recent cases:
https://www.vice.com/en/article/pkppqk/court-throws-out-mess...
https://www.computerweekly.com/news/252503524/Berlin-court-f...
Recent cases:
https://www.vice.com/en/article/pkppqk/court-throws-out-mess...
https://www.computerweekly.com/news/252503524/Berlin-court-f...