“They’re investigating.”

That’s what Colorado Secretary of State Wayne Williams said this week about the state attorney general’s office and a probe into what happened during Colorado’s Electoral College vote last year— four months after it took place.

On Dec. 19, 2016, during a traditional ceremony where the state’s nine national electors cast their official votes for president, one of them, Micheal Baca, did not cast his for Colorado’s popular vote-getter Hillary Clinton, and was stripped of his duties and replaced.

Four of Colorado’s nine electors— all of them Democrats— made headlines after Donald Trump’s election when they joined a national movement called the Hamilton Electors. The effort aimed to thwart Trump’s path to the White House through the Electoral College. The plan was to get enough electors nationwide to band together and vote for an alternate candidate— someone like Ohio Gov. John Kasich— and keep Trump from taking office.

To do so would would mean electors in 29 states would have had to violate state laws that require electors to vote for whichever candidate won their state’s popular vote. In Colorado that meant Clinton.

Related: The Electoral College plan to stop Trump explained

When the time of the vote came during a ceremony at the capitol in Denver, one elector, Micheal Baca, voted for Kasich instead of Clinton. Doing so made Baca the first elector in Colorado history to vote for someone who did not win the state’s popular vote. Secretary Williams immediately stripped Baca of his duties and Baca was replaced with another elector who cast a vote for Clinton.

Days later, Williams asked Republican Attorney General Cynthia Coffman’s office to investigate Baca.

“We had an individual who took a specific oath and then immediately violated the oath,” Williams said in an interview this week with The Colorado Independent. “And so I think we want the AG to investigate both the refusal to do our statutory duty and also the violation of the oath.”

Since December things have been quiet for the electors. They each went back to their normal lives after more than a month in the national spotlight.

In recent weeks, however, a state investigator has called at least three of them saying he is looking into what happened. The investigator declined to talk about it with The Independent, referring questions to the AG’s spokesperson. AG spokeswoman Annie Skinner declined to comment.

Related: Why is a state investigator sniffing around Colorado’s Electoral College vote?

“They’ve asked us some questions,” Williams said about the attorney general’s probe. He said his office has compiled data and provided copies of documents, but he didn’t elaborate about what they were.

“I think first and foremost Coloradans need to be able to trust that the people they elect are going to do their job,” Williams said when asked what he hopes comes of the probe. “People need to have the confidence that people aren’t going to lie and try to throw away their vote and discard the vote of 2.9 million Coloradans. So what I hope happens is, as with most sanctions, that it deters other people from trying to thwart the will of the people of Colorado.”

Micheal Baca declined to comment. His attorney, Mark Grueskin, did not immediately respond to a voicemail message.

State laws requiring national electors to vote for the presidential candidate who wins their state’s popular vote started popping up around the 1950s. Since then no one has been criminally prosecuted for violating such laws.

Three presidential electors in Washington State became faithless electors when they chose to vote for someone other than Clinton. A judge last month upheld fines— $1,000 each— against them for doing so.

Before the Electoral College vote, filmmaker Michael Moore said he would pay the fines for electors who went rogue.

Republican Electors — If you vote your conscience at noon and your state fines you for this, I will pay your fine: https://t.co/LIFVD4xjD4 — Michael Moore (@MMFlint) December 19, 2016

What could happen to Baca if the attorney general pursues charges against him is unclear.

“I think it’s going to come down to whether the state law is valid,” says Jason Wesoky, a Colorado attorney who is part of a legal group called Hamilton Defenders. In other words: Baca might not have voted for Clinton on Dec. 19 as state law required, but what if that state law was unconstitutional?

Wesoky was the lawyer who argued on behalf of two other Colorado electors, Colorado Springs Math teacher Bob Nemanich and former Denver lawmaker Polly Baca (no relation to Micheal), who sued Colorado in federal court saying the state law was unconstitutional.

That lawsuit is still pending.

State law allows Colorado to replace electors who go rogue, Wesoky says, but the 10th Circuit Court of Appeals has indicated it is unlikely Colorado could remove an elector after voting already began.

“The Constitution is pretty darn clear it is Congress that counts the votes, not Secretary Williams,” Wesoky says.

Bottom line: The saga of Colorado’s Hamilton Electors might not be over.