DECREES that the decision regarding whether or not to legalize prostitution shall be left to member nations to make within the confines of international law,
This critical sentence can be interpreted in two different senses:
2) The question of prostitution's legalization shall be decided by member-nations within the confines of international law -- this is to say, that member-nations shall be the arbiters of the issue, but not necessarily for each of their own nations.
The author obviously intended the first interpretation, but I actually think the second interpretation, the literal meaning, is more obvious -- I had to read the sentence several times before I understood it under the first interpretation.
This could have been avoided by using less roundabout language, like "member-nations shall have sole jurisdiction over whether to legalize, criminalize or decriminalize prostitution within their own nations".
There are two key failures, thus, that I see with "Clean Prostitute Act":
1) "Clean Prostitute Act" 's equivocation may completely undermine its status as a "blocker resolution". In fact, the blocker clause may be read as accomplishing the exact opposite thing that the author intended.
2) It's not actually a full blocker: it blocks the WA from discussing the legalization of prostitution, but not the decriminalization of prostitution. This is rather unfortunate, because the decriminalization of prostitution (without legalizing it), often threatens the health and safety of prostitutes more so than either legalization or prohibition. I also do not think the author intended to leave the question of decriminalization open for discussion.