Photo by Gabe Silverman/The Washington Post

Eighteen years ago, California became the first state to decriminalize weed for medicinal purposes. Twenty-three states and the District of Columbia have since followed. Of course, to openly purchase pot is to pay taxes for pot. Enter the black market sellers, who cater to people who’d rather not — and provide shadowy competition for the regulated industry. The Post’s Tina Griego takes you inside one Colo. man’s business:

The front door stays closed. The sheer white curtains in the living room window let in light, but nothing else. A basement filtering system vents air scrubbed of the sweet funky smell of the pot growing in the basement. He keeps his grow operation here small. It’s his home. That’s his grandson upstairs watching TV with strict instructions not to open the door if someone knocks. Should the cops inquire, they’d find a frail-looking, middle-age Latino with diabetes and heart problems, talking about his pension and his Medicaid and waving his medical marijuana registry card.”

We know Americans are smoking more marijuana. But how does that affect our health, culture and economy?

1. In Colorado, recreational weed costs twice as much as medical and black market weed.

The data: It on average sells for $400 an ounce. Medical goes for $200. Black market, $156.

The story: The Post’s Griego explains how new opportunity disparities fuel racial tensions:

“In any case, these first curious months of the legal recreational market have laid bare a socioeconomic fault line. Resentment bubbles in the neighborhoods where marijuana has always been easy to get, where the tenant grows his weed and one of his middlemen plans his own operation and says ‘everyone wants to be a weed man now.’

The sentiment goes something like: We Latinos and African Americans from the ‘hood were stigmatized for marijuana use, disdained and disproportionately prosecuted in the war on drugs. We grew up in the culture of marijuana, with grandmothers who made oil from the plants and rubbed it on arthritic hands.  We sold it as medicine, for profit and pleasure.

Now pot is legalized and who benefits? Rich people with their money to invest and their clean criminal records and 800 credit scores. And here we are again: on the outskirts of opportunity.”

2. Policy decisions that liberated pot smokers in Colorado are filling rural jails in Kansas.

The data: Police make a marijuana-related arrest once every 42 seconds, according to the latest FBI numbers.

The story: The Post’s Marc Fisher examines what happens when people buy pot where it’s legal and bring it home where it’s not:

“In Goodland, Kan., 20 miles from Colorado, four of the 18 men in Sheriff Burton Pianalto’s jail are there because they brought marijuana across the state line. By the end of April, Pianalto already had spent half his meals budget for the year. He’s not sure how he’ll pay for enough Lean Cuisine boxes to make it to December. It runs him $45 a day to house some kid from Minnesota or Illinois who bought weed legally in Colorado and started driving it back east on Interstate 70 to sell to friends.”

3.Those green-scrubbed “doctors” on the Venice boardwalk? They’re staying busy.

The data: In California, 75,200 people have medical marijuana cards.

The story: Writer David Samuels followed his old pal, a pot broker, for an intimate New Yorker look at how medical marijuana has changed the weed industry.

“Captain Blue is a pot broker. More precisely, he helps connect growers of high-grade marijuana upstate to the retail dispensaries that sell marijuana legally to Californians on a doctor’s recommendation. Since 1996, when a referendum known as Proposition 215 was approved by California voters, it has been legal, under California state law, for authorized patients to possess or cultivate the drug. The proposition also allowed a grower to cultivate marijuana for a patient, as long as he had been designated a “primary caregiver” by that patient. Although much of the public discussion centered on the needs of patients with cancer, AIDS, and other diseases that are synonymous with extraordinary suffering, the language of the proposition was intentionally broad, covering any medical condition for which a licensed physician might judge marijuana to be an appropriate remedy — insomnia, say, or attention-deficit disorder.”

4. Cannabis could create careers.

The data: For starters, the marijuana industry is expected to generate 10,000 jobs in Colorado.

The story: Wired’s Matt Honan writes about how entrepreneurs are harnessing this pot power.

“For the science and technology set, it’s a classic opportunity to disrupt an industry historically run by hippies and gangsters. And the entire tech-industrial complex is getting in on the action: investors, entrepreneurs, biotechnologists, scientists, industrial designers, electrical engineers, data analysts, software developers. Industry types with experience at Apple and Juniper and Silicon Valley Bank and Zynga and all manner of other companies are flocking to cannabis with the hopes of creating a breakout product for a burgeoning legitimate industry.”

5. Long before Snoop Dogg popularized the art form, a well-known scientist waxed poetic about weed.

The data: Marijuana lost its “hippies only” reputation decades ago. Today, an estimated 42.8 percent of Americans have tried it. More than half say it should be legal, according to Pew research.

The story: Astronomer Carl Sagan published this essay in 1969 under the pseudonym Mr. X.

“I can remember another early visual experience with cannabis, in which I viewed a candle flame and discovered in the heart of the flame, standing with magnificent indifference, the black-hatted and -cloaked Spanish gentleman who appears on the label of the Sandeman sherry bottle. Looking at fires when high, by the way, especially through one of those prism kaleidoscopes which image their surroundings, is an extraordinarily moving and beautiful experience.”