Tuesday, it was reported that Frank Gaffney, president and founder of the Center for Security Policy, had been named as an adviser to Donald Trump’s transition team. Wednesday morning, Trump officials are reportedly strenuously denying Gaffney’s on board. The slipperiness of what’s been happening with Trump’s transition suggests we should take their denials with a grain of salt. Tuesday, for instance, NBC’s Andrea Mitchell tweeted that Trump had requested a top secret clearance for his son-in-law, Jared Kushner. Wednesday morning, however, Trump denied those reports, contradicting a Trump official who had earlier said a low-level Trump staffer requested the clearance. If it is always hard to know what to believe when covering politics, it is now even more so. But even if Frank Gaffney’s not officially on the team technically speaking, it seems likely that he is or at least was in Trump’s transition orbit.

So just who is Gaffney and why would his hiring matter?

Anyone unsure about the extent to which Trump will follow through on proposals like the ban on Muslim immigration should be deeply troubled by Gaffney’s name floating around Trumpworld. For nearly two decades now, Gaffney has been one of America’s most successful professional Islamophobes, pushing wild conspiracy theories about Muslim infiltration through columns and regular appearances on Fox News that have acquired wide currency on the right-wing fringe. Like Trump, Gaffney was a birther. In a 2008 column for the Washington Times written weeks before Obama had even been elected, he advanced the idea that Obama had been born in Kenya and outlined his alleged ties to dangerous “Islamists.” These themes would be revisited again in an MSNBC appearance in which he claimed that Obama bowing to the king of Saudi Arabia was a code for submission to Sharia law that would be received in “the Taliban headquarters and in al Qaeda’s cave and in the kingdom of Saudi Arabia,” as well as a column following Obama’s 2009 Cairo speech in which Gaffney suggested Obama could well be a Muslim himself, in part because he had said the words Holy Quran four times during his address. The following year, he would claim that the logo of the Pentagon’s Missile Defense Agency had been changed to a fusion of Obama’s 2008 campaign logo and an Islamic crescent, an accusation so ridiculous he was forced to make a rare retraction and apology.

Gaffney and the Center for Security Policy spend perhaps most of their time warning the gullible about the spread of creeping Sharia and the machinations of the Muslim Brotherhood, which they claim has ties to Hillary Clinton through Huma Abedin and anti-tax zealot/brave vaper’s rights crusader Grover Norquist, whose wife is Palestinian-American. It was the latter claim that got Gaffney banned from the Conservative Political Action Conference in 2010. Gaffney, CPAC chairman David Keene said, had “become personally and tiresomely obsessed with his weird belief that anyone who doesn’t agree with him on everything all the time or treat him with the respect and deference he believes is his due, must be either ignorant of the dangers we face or, in extreme case [sic], dupes of the nation’s enemies.” But Gaffney was back at CPAC for this year’s conference to head a panel on—what else?—“Countering the Global Jihad,” which featured prominent European Islamophobes.

This isn’t actually the first time Gaffney and his work have been connected to Trump. When he announced his Muslim ban proposal last year, Trump cited a debunked poll from the Center for Security Policy that suggested significant numbers of American Muslims backed the imposition of Sharia law and violent jihad within the United States. Given all this, Gaffney’s going to be a figure to watch during the new administration whether or not Trump employs him. He’s one of the voices that’s brought us to this point, and is likely to be sounding the alarm against Muslims even more loudly in the next four years.