I don't trust the courts to determine which software "has no other purpose than to commit crimes". As I point out in another comment, penetration testers could

I don't trust the courts to determine which software "has no other purpose than to commit crimes". As I point out in another comment, penetration testers could argue that they'd legitimately need to use nearly any software used by hackers, including stuff like Metasploit. Someone else also points out it could potentially inhibit people disclosing vulnerabilities.