Lawmakers in Mexico City will introduce a bill on Thursday which would legalize the personal possession of marijuana in quantities of up to 5 grams, Animal Politico reported on Wednesday. Juan Francisco Torres Landa, general secretary of civil-society group México Unido Contra la Delincuencia (Mexico United Against Crime), which was involved in negotiations over the bill, told the site that the legislation aims to decriminalize without encouraging the consumption of pot. “It proposes for Mexico City to stop going after those who carry 5 grams of marijuana for personal consumption,” he said.  “To make an exception for a greater quantity would put the constitutionality of the initiative at risk.”

In 2009, Mexico decriminalized the possession of that quantity of pot (as well as up to 500 milligrams of cocaine and very small amounts of heroin and methamphetamines).  But while users can’t be prosecuted if they’ve only got that amount, they can be detained by police and turned over to public health authorities to attend treatment for addiction.  The new law effectively does away with that requirement.  “Its lenience is within that provided for by the General Law of Health” – the 2009 federal law, said Torres Landa.

The final version of this legislation is considerably more conservative than earlier drafts worked by on lawmakers with the leftist Party of the Democratic Revolution (PRD), who had said they were inspired by the passage of legislation in Colorado, Denver and Uruguay.  Two lawmakers had told Mexican media that they saw Colorado’s establishment of a 25 percent sales tax on marijuana as a potential model.  The bill’s sponsors may have been dissuaded of the legality of the idea, which would have based itself upon a constitutional right for local authorities to set their own law-enforcement priorities – marijuana would have become a “zero priority”.