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yea
I have never heard of any legitimate evidence of negative effects, especially that would justify coercive state intervention

Ah, there is evidence to suggest that the non-existent CBD levels and the artificially high levels of THC in strains of skunk might be causing some mental health difficulties in adolescent boys. It isn't conclusive, but certainly warrants more study.

yea but i mean cause or symptom? correlation i dont know if that is good evidence?

Cause, it would appear:

https://www.theguardian.com/society/2015/feb/16/skunk-cannabis-triples-risk-psychotic-episodes-study

And there is plenty more. And this discusses how important CBD is:

https://www.newscientist.com/article/dn26988-skunks-psychosis-link-is-only-half-the-cannabis-story/

I am not anti-drugs (especially not anti-cannabis) by any means, and I realise that a lot of smokers won't find it easy to accept. But the evidence is stacking up.

Do your own research, if you are really seeking a balanced view.