The state of California is trying a new approach to slow down a fast growing illegal marijuana market. State regulators are proposing a requirement that legal pot shops post a black-and-white display known as a "QR" code in their storefront window, so customers can quickly identify legally licensed businesses with tested cannabis products by scanning the code with their smartphone.
Marijuana became legal to sell in California in 2018. However, the illegal market continues to flourish, and officials said rogue pot shops are easy to find in Los Angeles and other cities.