Do politicians not realize how severe a prison sentence is? 
1) It costs taxpayers a fortune
2) It causes a person to lose their current job
3) It damages their chances at employment upon release
4) It hurts the innocent dependents of the jailed person
5) It exposes the criminal to other criminals who most likely committed far worse crimes
6) It limits a person's economic output

Now does it make sense to jail someone for even a few weeks never mind 14 years for providing cannabis to a minor? Doe it even make sense to jail people at all except in cases of violent crimes? No. 
Prison sentences are old fashion and need to be abolished for most crimes. Community services/fines would be far more effective.