well a potential argument for and against that it can lead to worse drugs can work both ways
the one for saying it shouldnt be legalized deals with the drug itself leading onto worse drugs, but i dont really believe that
the one for saying it should be legalized deals not with cannabis itself, but the ways in which it has to be bought whilst being illegal
With cannabis being illegal, you can only get it through underground, dealers etc. The general way in which other illegal drugs are bought is the same, so just by learning to get cannabis you are learning how to get the other drugs and no doubt at some point (unless the dealer is strictly cannabis only) would likely offer the person another drug and they might or might not accept. If they accept then they are leading onto worse drugs
If cannabis was legalized, then you wouldnt need to get it from dealers and wouldnt be offered the other drugs at some point so likely you wouldnt lead onto other drugs this way.
Plus i love cannabis, and i'd prefer it to be legal for the fact i could buy it legally and wouldnt get arrested for having it :p
Another gray area of the law (atleast in UK), its legal to smoke it in your own home, but illegal to have it with you in public places.
That is a bit contradictory since the only way to get it to your home to be smoked/cooked with whatever would be to buy it from a dealer and carry it with you home (I doubt the dealer is going to do home deliveries :p). So probable that you are going to be in possession of it in a public place and then you get arrested if caught.
Story about my brother, he had been at work all morning, went off for his 1 1/2 hour break before going back to work until the end of the day, he was turning into the carpark about 4 buildings down from restaurant, police stop him because his tail light was out. They smell cannabis on him and check him and he had a small ammount in his shirt pocket and the car no doubt smelt of it. Even though he hadnt been smoking it that day, they still arrested him even though he was basicly at work now and my mam had said he had been at work all morning (parent's restaurant) and was at police station in cell for 2 hours. On another occasion for same offence he was in cell for 6 hours before being released.