When the phone rang in George David Banks' office at 4:30 Tuesday afternoon, the White House counsel's office was on the line: Could Banks come to a meeting at 6 p.m.?
The call was the first indication that something had gone very wrong for Banks, an environmental policy advisor in the Trump administration. Later, he would resign after finding out that he did not qualify for a permanent security clearance because of past marijuana use.
It was the third White House resignation within a week which centered on an aide's security clearance.
Staff secretary Rob Porter quit last week after reports emerged that his two ex-wives accused him of domestic abuse. Speechwriter David Sorensen, meanwhile, resigned Friday after his ex-wife said he had abused her. Both Porter and Sorensen denied the accusations.
Banks, on the other hand, had voluntarily disclosed that he smoked marijuana a few years prior, according to a source familiar with the situation who declined to be named.
Banks, who was a special assistant to the president for international energy and environmental policy on the National Economic Council, had been one of the key figures in developing the Trump administration's policy on the Paris climate accord.
In his year at the Trump White House, Banks had been operating on an interim security clearance. He had followed the typical procedures for new employees after starting work in February 2017, filling out an SF-86 form detailing his personal background.
The source told CNBC that Banks disclosed on the form that he had smoked marijuana as recently as 2013. In the spring of 2017, FBI agents visited Banks in his office to go over the information on the form. The meeting lasted about an hour, a source said.
But it wasn't until this week that the marijuana disclosure apparently came back to haunt Banks. The source said the White House counsel's office told Banks he had been denied a permanent security clearance, and could not do his job without one. The marijuana use, the counsel's office said, was simply too recent to permit a permanent security clearance.
Banks was left with little choice but to resign. The source familiar with the events describes him as "shocked" by what happened.
A White House official declined to comment.
In the wake of the Porter firing, several other administration officials may be just as shocked in coming weeks, as the White House struggles to deal with officials who have not been able to qualify for a permanent security clearance for a variety of reasons.
It's not clear what will happen next for Banks. The source said he was told the administration would still be able to hire him elsewhere and encouraged to apply for jobs that do not require a security clearance.