I think weed in itself is bad enough if you abuse it. there has long been a link associating cannabis with psychosis and I have seen it happen to a couple of people with my own eyes. so I don't care who says weed is harmless...its a lie. I dont care who smokes it down just don't delude yourself:

check this link out:

http://www.healthtalk.ca/psychosis_12012004_7023.php

With regards to the question I think that sometimes it can lead to harsher things with people who are open to experimentation, have addictive personalities and a void to fill in their lives. I have seen this too.