Not exactly, hence the rise of fentanyl. Prior to the rise of fentanyl, new addicts often went from prescription pills like oxycodone to heroin as their lives unraveled because prescription drugs are expensive and hard to get. Some enterprising drug dealers started enhancing their cut heroin with fentanyl which can be imported from China and is extremely dense compared to other opiates, which matters because smuggling is most of the cost. Downward pressure on the prices changed the ratio until you were left with pure fentanyl, so in effect prescription pills were not available enough and drug dealers were able to capture the market with more dangerous but cheaper product.

'illegal drugs' is a pretty broad brush, and treating opiods and psychedelics equivalently is silly. Surely treatment, education and research would all be far easier alongside decriminalization?

"Illegal drugs increase crime, partly because some users turn to crime to pay for their habits "

If all drugs would be illegal, then they would be mostly so cheap that this argument falls apart very quickly. Drugs are only expensive because they are illegal. Poppy and coca are not hard to grow and neither is hemp. And the chemical drugs are way more cheap to produce. So very high quality stuff would remain expensive, the same way a fine wine is expensive, but just to get drunk is cheap (even with taxes).

"and partly because some users are stimulated by certain drugs to act more violently."

And yes, that is true, but one of the most famous and widespread drug that makes people aggressive is already legal - alcohol.

"Legalization, however, will not affect addiction"

And this is up for debate, for some it will be easier to get help, because the stigma and criminalisation is gone, but yes, some might start it, because it becomes avaiable. And I did not look in the recent numbers, but back then when I did - in the netherlands for example, drug use decreased, after marijuhana was legalised. It is quite complex - some people are afraid of anything illegal, some are appealed by it, mainly teenagers who are in most danger of becoming addicts/developing brain damage.

"better treatment, education, and research are needed to curb dependency on drugs and the adverse health and social effects of drug use."

But this is true. And better, than jail people who simply need help.

That bit about Purdue resonates with me. I'm not firmly against legalization of harder drugs, but that's a case where average people given legal access to pharmaceutical-grade medicine through proper legal venues has been absolutely catastrophic. If I were making a case against legalization, that would be my Exhibit A.

> - The black market is always cheaper.

anecdata: I'm in canada, which has legalized marijuana recently. The black market is cheaper, but all but the most die-hard stoners I know like to buy government weed, because the product is consistent and you know what you're getting.

> - Even in a legal market how many people are always buying their own?

Maybe I'm misunderstanding, but in a legal market even if I don't buy something directly at least I have vastly increased faith that i know what something is.

> - If everything is legal then it's even easier for people to spike drinks and the like.

Who knows, but I strongly doubt that there is a large pool of potential rapists at large who are currently stymied primarily due to the difficulty in acquiring GHB.

> - Purdue Pharma marketing issue writ large. > - Patients pressuring their doctors to prescribe, or alternatively feeling pressured by their doctors to use a particular drug.

There are definitely a bunch of social and policy questions that would need to be addressed when considering legalization, sure.

> - If it's legal it's easier to purposefully or accidentally overdose (e.g. alcohol today). Especially if it's also cheaper.

Almost certainly not, as the majority of overdoses are the consequence of people not knowing what they're taking, or not knowing how to take it.