BUFFALO, N.Y. (WIVB) On Monday, Rep. Chris Collins (R-27) submitted his letter of resignation, announcing that he is stepping down effective immediately.

The news came hours after News 4 confirmed that a plea change hearing has been scheduled for Tuesday for Collins, his son Cameron, and Cameron’s fiance’s father Stephen Zarsky in the insider trading case against them. The three originally pleaded not guilty to the charges.

Here’s a timeline of the events leading up to Collins’ resignation:

June 22, 2017

Rep. Chris Collins attends the congressional picnic at the White House. The indictment against him states he made phone calls to his son about the stock in question while at the picnic.

Collins can be seen talking on his phone in this video.

Oct. 12, 2017

The House Ethics Committee says they have “substantial reason to believe” Chris Collins “shared material nonpublic information.” A spokesperson for Collins said the accusations against him are false, and called the move a political witch hunt.

Aug. 8, 2018

Rep. Chris Collins was charged with insider trading: In a criminal complaint, federal prosecutors accused Collins, who served on the board of an Australian biotech company, of telling his son Cameron about negative results of some of the company’s clinical trials before they were released to the public. After the results went public, the company’s stock dropped 90 percent in one day.

Collins, Cameron Collins, and Zarsky were each charged with conspiracy, securities fraud, wire fraud, and making false statements to the FBI.

Aug. 11, 2018

Collins announces he will suspend his re-election campaign, but maintains that he is innocent.

Sept. 9, 2018

A month after his indictment, Collins speaks exclusively with News 4’s Dave Greber.

Sept. 19, 2018

Collins reverses course and says he will actively run for re-election in November.

Nov. 1, 2019

A representative for Collins announces that the Congressman will not debate his opponent, Democrat Nate McMurray.

Nov. 6, 2018

Collins narrowly defeats McMurray in race for 27th Congressional District.

Aug. 6, 2019

In a new indictment, some of the security fraud charges against Collins and Cameron Collins are dropped.

Sept. 10, 2019

Pretrial motions in Collins’case came back against the congressman. A federal judge ruled that the information used to charge Collins isn’t protected under federal law because the searches didn’t involve official accounts or congressional offices.

Sept. 12, 2019

For the first time since his indictment, Collins misses a vote in Washington to be in court. Outside of court, Collins maintains innocence, says he is undecided about running for re-election but is confident if he did run he would “win in a landslide”.

Collins is due to appear in court Tuesday. Check back on our website and social media pages for the latest updates.