Colorado is ground zero for America's experiment with legalized marijuana and, according to a Washington Post article, the black market for pot in Colorado has not taken a hit after legalization. Instead, it's flourishing.

Tina Griego, the Post reporter who wrote the story, joined Bill O’Reilly on tonight’s “Factor” to discuss what she found in her research.

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Griego said the primary reason for the marijuana black market is that it’s extremely lucrative to purchase or grow pot in Colorado and turn a profit by moving it to other states, sometimes with the help of a pot “broker” who will act as liaison.

Another reason for the black market, according to Griego, is the extremely high rate of taxation for a recreational marijuana card. This has led to large numbers of people using only the lesser-taxed medical marijuana card or turning to the black market to avoid taxes.

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O’Reilly said an issue that arose in California when it legalized medical marijuana was drug addicts getting it legally and selling it to children to get money for harder drugs, but Griego said she did not encounter that while researching the pot black market in Colorado.

However, she left no doubt that there is an illegal marijuana market flourishing beneath the cover of the legal marijuana market in Colorado.

Watch the whole clip above.

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