Long before I began this project, I had steadily reviewed the scientific literature on medical marijuana from the United States and thought it was fairly unimpressive. Reading these papers five years ago, it was hard to make a case for medicinal marijuana. I even wrote about this in a TIME magazine article, back in 2009, titled “Why I would Vote No on Pot.”

Well, I am here to apologize.

I apologize because I didn’t look hard enough, until now. I didn’t look far enough. I didn’t review papers from smaller labs in other countries doing some remarkable research, and I was too dismissive of the loud chorus of legitimate patients whose symptoms improved on cannabis.

What Gupta did is commendable. It is never easy for people to admit they were wrong. Acknowledging that new facts requires you to change your position and admitting your past errors is sadly too rare.

Hopefully, Gupta’s very public example will encourage other prominent figures and government officials to truly examine the evidence. At one point President Obama was seriously considering naming Gupta Surgeon General. It would be nice if Obama would listen to him now.

In his apology Gupta shows that the federal government lacks any scientific justification for keeping cannabis a Schedule I drug, which makes medical marijuana illegal under federal law. The Obama administration has the legal authority to resche