It can be hard to tell in some cities, but public drinking is illegal in much of the US.

As the Huffington Post's investigation uncovered, hundreds of thousands, if not millions, of people are arrested or ticketed under these bans each year. And what counts as a public space under the bans — a street, sidewalk, park, beach, or stadium — can vary wildly from state to state and city to city, even from block to block.

Many of these restrictions came about after states and cities repealed bans on public drunkenness. Many legal scholars argued the public drunkenness laws wasted police and court resources, were disproportionately enforced against minorities and poor people, and tried to address issues of alcohol abuse that are better left to health and religious institutions rather than the criminal justice system.

Of course, public drinking laws have many of the same problems: in a review of a month's worth of public drinking tickets in Brooklyn, a New York City judge's staff in 2012 found that, as reported by the New York Times, "85 percent of the summonses were issued to blacks and Latinos, while only 4 percent were issued to whites" — even though 36 percent of Brooklyn's population is white.

But that hasn't stopped some states and cities from enforcing the laws — although some police officers might take a more relaxed approach during holidays like St. Patrick's Day and Cinco de Mayo, or the bans might not be enforced very harshly at all.

Further reading: 35 maps and charts that explain alcohol.