Request: History of the German drug regulation law.

The book opens with two excerpts, respectively, of the Charge and the Verdict against Christiane.

“[…] The student Christiane Vera F. is charged as a legally responsible juvenile with having used regulated narcotic substances continuously after May 20, 1976, without authorization by the Federal Department of Health. […]”

Zoo Station: The Story of Christiane F. by Christiane Vera Felscherinow, Kai Hermann, Horst Rieck. Zest Books LLC, San Francisco 2013.

I would like to explain how the law has changed over the years to arrive at the decriminalization of consumption. Nothing too sophisticated: I need the sources (possibly in English), some relevant dates and the current state of the law.

Or, if you are a lawyer or a law expert and are available to write the note you are welcome.