No, they aren't the same. Unfortunately, googling decriminalization vs legalization gets me articles that state the exact opposite of my understanding. As I understand it, decriminalization means making no law against it. Legalization means making laws about it that boil down to regulation. Thus, decriminalization is more free.

This article seems to be generally in line with my understanding:

http://time.com/3005687/what-the-swedish-model-gets-wrong-ab...

Example of making it worse: From what I gather, prostitution in Las Vegas is mostly run by the mafia and legalization has not led to women being free to be their own boss, set their own hours, etc. Legalization of prostitution often means sex workers are subjected to a lot of rules and regulations such that it becomes akin to wage slavery rather than freedom to pursue work independently like a small business owner.

I will suggest Obamacare as another example of regulation making things worse. I'm quite poor and being hit with harsh financial penalties on my taxes this year for failing to have full coverage for all of last year. Prior to Obamacare, I could just forego having healthcare and the government did not get all up in my business about why I did that and whether or not I was allowed to do that, etc.

My support of decriminalization of prostitution comes from having read Working: My Life as a Prostitute by Dolores French. Prior to becoming a prostitute, she was a political activist.