Friday, December 19, 2014

4/20, America's stoner holiday, explained

A crowd celebrates 4/20 at Hippie Hill in a San Francisco park. Justin Sullivan / Getty Images News

While most Americans are observing Easter and Passover this weekend, thousands are hitting the streets of Denver and other American cities to celebrate a less traditional holiday: 4/20.

The holiday is cherished by marijuana enthusiasts around the world, and this year is no different. The rallies in Denver and other Colorado cities are poised to be the biggest yet, in large part due to the legalization of marijuana in the state.

What is 4/20?

For some, 4/20 is a moment to protest social and legal stigmas against marijuana. For others, 4/20 is just a chance to get high with a bunch of their friends.


A protester holds up a sign during Denver's 2010 4/20 rally. Joe Amon / The Denver Post

Keith Humphreys, a psychiatry and behavioral sciences professor at Stanford University, says the holiday is a continuation of the counterculture movement that embraced marijuana, using the drug as a symbol to protest against broader systemic problems in the US.

"Marijuana was the way you said you weren’t a suit," Humphreys says.

Legal marijuana activists have tried to bring a more formal aspect to the celebration, framing it as a moment to push their political agenda. Organizers for the Denver rally, which is expected to be the largest this year, framed their cause in somewhat grandiose terms. They put out a statement comparing the battle for legal marijuana to "the time when Jews fled from slavery in Egypt," a moment commemorated in Passover celebrations.

"This year’s rally represents the continuing fight for freedom from economic slavery for marginalized members of our community and a rebirth of creative genius that will get us there," Denver rally organizers wrote.

Of course, many people are attending the rally just to party and have some fun. "I suspect most people are in Denver because they want to get high," Humphreys says.

Why 4/20?

There are a few theories as to why marijuana enthusiasts' day of celebration landed on April 20 in particular, but the real origin remains a mystery in marijuana lore.

The most commonly held belief is that 420 was the California police code for marijuana, but there's no evidence to support that claim.

Another theory is that there are 420 active chemicals in marijuana, hence an obvious connection between the drug and the number. But there are more than 500 active ingredients in marijuana, and only about 70 or so are cannabinoids unique to the plant, according to the Dutch Association for Legal Cannabis and Its Constituents as Medicine.

Steven Hagen, former editor of High Times, told The New York Times that the holiday came out of a ritual started by a group of high school students in the 1970s. As Hagen tells it, some Californian teenagers ritualistically smoked marijuana every day at 4:20 p.m. The ritual eventually spread, and soon 420 became code for smoking marijuana. After 420 was converted into 4/20 for calendar purposes, the day of celebration was born. (It's worth noting, however, that there's little evidence to prove Hagen's story beyond the claims of a group of Californians who took credit for 420's origin.)

Where is 4/20 a big deal?

Since it supposedly originated in California, you can probably guess that 4/20 is a big deal among marijuana enthusiasts there. But the celebration has really spread all over the country, particularly in the western states.


A crowd celebrates 4/20 in Denver. Justin Sullivan / Getty Images News

This year, the most prominent 4/20 celebration is in Denver. Following Colorado's decision to legalize marijuana, Denver became the largest city to allow the retail sales of recreational marijuana. That made Denver the center of the legalization movement and, as a result, the capital of 4/20 celebrations in the US.

Is 4/20 changing after legalization?

For many, 4/20 started as a counterculture holiday to protest the social and legal stigmas against marijuana. In that sense, marijuana legalization could undercut the whole point of the celebration.

But at least for this year, it seems people from around the world are going to Denver to celebrate specifically because of the legal status.

Some people might be going there to protest legal restrictions in their home states and countries, and a lot of them might appreciate the novelty of legalization in Colorado. But most of them, Stanford's Humphreys suspects, just want to get high without the risk of running against the law.

Humphreys speculates that the novelty of legalization and the idea of taking one day off to celebrate marijuana will eventually wear off. After all, people don't typically take one day of the year to celebrate alcohol. (Well, maybe St. Patrick's Day.)

The biggest flip, however, could come once big corporations begin selling marijuana, much like alcohol and tobacco companies. Humphreys says that change, more than anything, will solidify the end of marijuana as a counterculture symbol. Once that happens, he suggests the end of 4/20 will come quickly.

So what's happening in Denver for 4/20?

The city is now, by several accounts, in the middle of a massive 4/20 celebration as tens of thousands turn up to celebrate the first year of legal recreational marijuana sales in Denver and other parts of Colorado.

Rally organizers told a Denver television station they expect 80,000 people to attend this weekend.

The holiday apparently caused a flurry of interest in traveling to Denver. reported that hotel searches for the weekend of 4/20 were up 73 percent compared to the same time last year. Between January and March, hotel searches for Denver were also up 25 percent compared to the same time last year — another trend that attributed to marijuana legalization.

The Cannabist keeps a list of all the events scheduled for the weekend. Among the 47 events listed are a 4/20 rally, comedy shows (including Cheech and Chong), various concerts (including Snoop Dogg and Whiz Khalifa), 420-friendly speed dating, a marijuana-friendly trade show, and a variety of festivals and parties.

And, of course, there's the well-known group smoke: every year, participants count down to 4:20 p.m. and then simultaneously light up their joints, pipes, or whatever else they have on-hand.


Marijuana smoke looms over a Denver crowd after 4:20 p.m. on April 20, 2013. Chris Hondros / Getty Images News

One thing to keep in mind: public smoking is still illegal in Denver. Law enforcement officials said they will discourage people from smoking in public, but they also vowed to exercise discretion.

But if the event keeps with tradition, there are going to be a lot of people smoking in public. So expect a lot of pungent smoke — or odorless vapor, if people are using vape pens — in the air, especially after the 4:20 p.m. group smoke.

Isn't a large gathering of intoxicated people dangerous?

Any large gathering poses risks to public safety, which is one of the reasons these kind of events require permits in the first place. But marijuana, unlike alcohol, isn't typically attributed to violence, as researcher Robert Morris told me for a previous story.

Last year's event in Denver, however, was marked by tragedy when a shooter injured three people. Rally organizer Miguel Lopez recounted that the shooting was particularly terrifying for 4/20 celebrators because it happened shortly after the Boston marathon bombings.


A crowd runs away from gunshots at Denver's 2013 4/20 rally. Joe Amon / The Denver Post

To avoid a similar tragedy, Denver Police are stepping up their presence at the celebrations, and organizers told media they will bring their own security.

It's worth pointing out, however, that dozens of 4/20 rallies ran across the country in the past few years, including some in Denver, without major reports of violence.

So where can I sign up?

It's probably too late for this year, unless you live in Denver or another city holding a 4/20 rally. But if interest in the event continues climbing after legalization, as's data suggests, it's probably a good idea to be a bit forward-looking with your airplane and hotel bookings for next year's rallies. And keep in mind that, although many of the 4/20 events are open to the public, some do charge a fee for entry.

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