>>109619931) People will consume drugs regardless of their legal status.
2) There is no effective way to police their distribution and consumption without operating a police state.
3) Legalization means new sources of tax revenue
4) Legalization reduces your legal systems burden
5) Legalization comes with standardization and regulation, which equates to safer consumption.
6) Legalization creates jobs as you are now creating an industry
7) Legalization reduces the rates of criminality and the influence of criminal groups
Off the top of my head, this took me 30 seconds to come up with and it is bore out by the statistical data of the last 100 years globally and the historical data going back 2 thousand years.