Turkey's slide into Islamist authoritarianism makes it the odd man out in NATO.

At the Middle East Forum, we just finished hosting a conference for members of the NATO Parliamentary Assembly. A group of legislators who gather in Brussels to deliberate on the problems confronting the transatlantic partnership, this body seeks to uphold the same values that are supposed to underpin the transatlantic alliance: democracy, freedom of speech, freedom of the press, independence of the judiciary and protection of minorities.

Except it doesn't. Less than a week before our event was scheduled to begin, we received a call from the NATO Parliamentary Assembly with an uncomfortable demand. At the request of the Turkish government, the NATO Parliamentary Assembly demanded that we censor our program to remove a scholar named Emre Çelik. And unless we agreed, it was prepared to cancel the engagement entirely.

This was troubling from a logistical standpoint, of course. We'd spent a lot of money and a lot of time preparing for this event already. But it's troubling at a much more foundational level, too. If the nations sending delegates to the NATO Parliamentary Assembly truly believed in the values listed above, they would have rejected any such request from Recip Tayyip Erdoğan.

Why are NATO's legislative partners afraid to stand up for democracy and freedom?

If NATO's legislative partners are afraid to stand up when one of its own members violates key principles, then what's the point of the alliance? Perhaps most importantly, why is Turkey allowed to stay a member of NATO as the country completes its slide into Islamist authoritarianism?

So, we at the Middle East Forum were faced with a difficult decision. Either stand up for the values we believe in or kowtow to the very people we believe pose the gravest danger to civilized society in the West. It was truly a hard decision. And we decided to find a third option: We lied to protect our constitutional freedoms.

Çelik is the president of an organization called the Rumi Forum. Exiled cleric and top Erdoğan dissident Fethullah Gülen serves as honorary chair of the group. Gülen, you'll remember is the one Erdoğan blamed for the failed 2016 coup attempt without any evidence at all. Intelligence officials in the European Union and the chairman of the U.S. House Intelligence Committee have both expressed their doubts that Gülen was involved.

We had invited Çelik to speak because we believe that hearing diverse opinions is valuable. And Erdoğan's reign has led Turkey down a seriously bad path when it comes to the values that we are supposed to share with all NATO members. We also have a strong reaction when we hear Erdoğan's son-in-law, a cabinet minister in the government, say of Gülenists, "I would strangle them wherever I see them."

The Turkish delegation interrupted the proceedings when Çelik was invited to the podium, then stormed out.

In light of all this, we thought Çelik's insight was useful, and that his willingness to share it in a room including officials from the Turkish government was brave. We decided to stand up for our values, and although we removed him from the program, we brought him in as a surprise speaker.

When Middle East forum founder and president Daniel Pipes introduced Çelik, the reaction was predictable. The Turks in the room stood up and screamed. The co-leader of the NATO Parliamentary Assembly delegation expressed his disappointment, gave his final remarks, and then the entire NATO Parliamentary Assembly delegation walked out. They didn't hear what Çelik had to say, nor did they engage in a debate over the future of the alliance. Does that sound like the actions of people who share our Western values?

Turkey, a NATO ally, has jailed more journalists than China.

President Erdoğan is an Islamist. He spent the past 15 years working to dismantle Turkey's democratic institutions and arresting anyone who has tried to stop him. Turkey, a NATO ally, has jailed more journalists than China and thrown thousands of students in prison for speaking out.

Erdoğan has expressed strong support for Hamas and other Muslim Brotherhood-linked terror organizations. Turkey has prevented the U.S. from using its airspace in the fight against ISIS. It recently purchased Russia's S-400 missile defense system, a move that should require approval by the rest of NATO for reasons of force interoperability, though no such approval was ever even sought. And let's not forget that 15 of Erdoğan's security guards still face charges for the savage beating of peaceful protesters outside the Turkish embassy in Washington last May.

Unfortunately, what started out as a great honor for MEF devolved into yet another controversy. Freedom of speech is integral to how the Forum conducts its affairs and should be integral to any serious discussion of the challenges facing NATO. That's why we refused to let Turkey censor our event. But NATO's parliamentary vanguard seemed fine with it. Perhaps that's the most troubling part of all.

Gregg Roman is director of the Middle East Forum.