Others argue that it can lead to an increase in drug abuse and crime.

There's zero evidence for the above. In fact, there's probably evidence to the contrary. The Netherlands have had it legal for a long time and there's no difference in drug use between that country and, say, the UK. Also, there are just as many people smoking weed in the UK regardless of legal status.

By the way, I don't smoke and I hate the smell of weed, but objectively it's less harmful than alcohol for instance, and who will ever consider banning that in a non-Islamic country? It can even be argued that it's less harmful than plain old cigarettes. There really isn't any sound argument against it's illegality, considering all the other much more harmful stuff we're allowed to consume; sugar (high fructose corn syrup), Fluoride, mercury, etc.