Mexico's Supreme Court on Wednesday deemed the country's marijuana prohibition law unconstitutional, bringing America's neighbor one step closer to marijuana legalization.

It was not the first time the court made such a ruling, but it was the fifth time - a crucial threshold in Mexico. Under the country's legal system, once the Supreme Court reaches a similar decision in five separate cases, the standard set by the rulings applies to the country's entire court system.

As the Associated Press explained, "The rulings technically do not legalize recreational use, however. They establish that courts must allow it, but it is still up to each individual to press his or her case in the judicial system." The rulings apply to possession, use, and growing - not commercialization or sales.

The Supreme Court "found that adults have a fundamental right to personal development which lets them decide their recreational activities without interference from the state," the AP reported. The right is not absolute, and it does not apply to all substances - but it does mean that total marijuana prohibition is unconstitutional.

Mexican lawmakers could react to the ruling by adjusting the law to regulate marijuana under the new legal framework set by the Supreme Court. Officials in President-elect Andrés Manuel López Obrador's government have indicated that they may legalize marijuana, Reuters reported.

If Mexico's government follows through, the country could become the third in the world to legalize pot for recreational purposes - after Uruguay and Canada.

Although nine states in the US have legalized marijuana for recreational purposes, pot is still illegal under federal law in America.

Supporters of legalization argue that it eliminates the harms of marijuana prohibition: the arrests over a relatively harmless drug (and the racial disparities involved in America), and the billions of dollars that flow from the black market for marijuana to drug cartels that then use the money for violent operations around the world. All of this, legalization advocates say, will outweigh any of the potential downsides - like increased cannabis use - that might come with legalization.

Opponents, meanwhile, claim that legalization will enable a huge marijuana industry that will market the drug irresponsibly. They point to countries' experiences with the alcohol and tobacco industries, which have built their financial empires in large part on some of the heaviest consumers of their products. This could result in far more people using pot, even if it leads to negative health consequences.

At least in Mexico, the supporters won a big victory this week.

For more on marijuana legalization, read Vox's explainer.