Here's the damning timeline of Trump's blatantly corrupt Ukrainian collusion

While much of the push for removing President Donald Trump from office has focused on the events described in former Special Counsel Robert Mueller's report, Speaker Nancy Pelosi finally announced that the House of Representatives will begin an "official impeachment inquiry" on Tuesday by specifically citing another impeachable incident entirely.

Trump now finds himself neck-deep in a scandal about his efforts to encourage Ukraine to go after former Vice President Joe Biden; specifically, the president and his team have been urging for an investigation of the events surrounding the work of Biden's son, Hunter Biden, on the board of the oil company Burisma. Conservatives have been spinning a conspiracy theory that the former vice president somehow protected his son while carrying out the Obama administration's diplomacy in Ukraine, which involved applying pressure for the removal of a prosecutor in 2016 who was widely believed to be corrupt.

But much worse than promoting a conspiracy theory, Trump and his allies have pushed for Ukraine to conduct a formal investigation of Biden's son and, whether explicitly or by corollary and implication, the former vice president himself. This appears to be a blatant abuse of his authority, using the power of the presidency to induce a foreign country into investigating a political opponent. Worse still, this effort appears to not only have the implicit power of the presidency behind it, but the official force of the White House, because at the same time, Trump has been withholding authorized military aid to Ukraine.

This scandal has been covered far less the Russia investigation, and only recently has it become a leading story, so it's natural that the public may be a bit caught off guard and confused at the series of events. To get caught up, here's a timeline of key events in the scandal — along with links for further information:

• March 2019 — Prosecutor General Yuriy Lutsenko of Ukraine decides to reopen an investigation into Burisma, an oil company where former Vice President Joe Biden's son served as a member of the board. The New York Times reported that some saw this as an effort to "curry favor from the Trump administration for his boss and ally, the incumbent president, Petro O. Poroshenko."
• April 21, 2019 — Poroshenko loses his re-election bid to comedian Volodymyr Zelensky.
• May 1, 2019 — The New York Times reports on the Trump team's efforts to induce Ukraine to go after the Biden family:

  The Trump team’s efforts to draw attention to the Bidens’ work in Ukraine, which is already yielding coverage in conservative media, has been led partly by Rudolph W. Giuliani, who served as a lawyer for Mr. Trump in the investigation by the special counsel, Robert S. Mueller III. Mr. Giuliani’s involvement raises questions about whether Mr. Trump is endorsing an effort to push a foreign government to proceed with a case that could hurt a political opponent at home.

  Mr. Giuliani has discussed the Burisma investigation, and its intersection with the Bidens, with the ousted Ukrainian prosecutor general and the current prosecutor. He met with the current prosecutor multiple times in New York this year. The current prosecutor general later told associates that, during one of the meetings, Mr. Giuliani called Mr. Trump excitedly to brief him on his findings, according to people familiar with the conversations.

  Mr. Giuliani declined to comment on any such phone call with Mr. Trump, but acknowledged that he has discussed the matter with the president on multiple occasions. Mr. Trump, in turn, recently suggested he would like Attorney General William P. Barr to look into the material gathered by the Ukrainian prosecutors — echoing repeated calls from Mr. Giuliani for the Justice Department to investigate the Bidens’ Ukrainian work and other connections between Ukraine and the United States.

• May 2, 2019 — Trump retweets a link to the New York Times article about the Biden case and Giuliani's efforts to press for the investigation.
• May 7, 2019 — Bloomberg reported that the supposed conflict of interest case against Biden makes little sense. The case against Burisma, the company whose board his son served on, had been "dormant" long before the vice president got involved in advocating the prosecutor's dismissal.
• May 9, 2019 — Giuliani told the New York Times that he will go to Kiev to meet with then-President-elect Volodymyr Zelensky to insist that he pursue "two matters of intense interest to Mr. Trump" — one of which was the Biden investigation. "We’re not meddling in an election, we’re meddling in an investigation, which we have a right to do,” Giuliani said.
• May 10, 2019 — Trump said it would be perfectly appropriate for him to talk to Attorney General Bill Barr about prosecuting Joe Biden. Giuliani announced he was canceling his trip to Ukraine after receiving blowback from Democrats; he also suggested he realized the meeting would be "useless" because Zelensky was working with "avowed enemies of Pres Trump," Politico reported.

  “I have not spoken to him at any great length, but I will,” Trump told Politico that day of Giuliani's efforts in Ukraine. “I will speak to him about it before he leaves.”

• May 11, 2019 — Trump retweets former Gov. Mike Huckabee's call for the Senate Intelligence Committee chair to investigate "Biden's cushy deals w/ Ukraine & China while VP."
• May 11, 2019 — Separately, Serhiy Leshchenko, a Zelensky adviser, argued that Lutsenko had misled Giuliani about the Burisma case. The Associated Press reported:

  Writing in the Ukrainska Pravda online newspaper, Leshchenko said Lutsenko “came up with the story” that the former vice president had pressured Ukraine to close the case involving the gas company, while it was Lutsenko himself who had closed the case more than two years ago. He re-opened the case this spring in the midst of Ukraine’s presidential campaign in what was seen as an effort to win Trump administration support for Poroshenko.

• May 16, 2019 — Bloomberg reported that the Ukrainian Prosecutor General Lutsenko said he had seen "no evidence of wrongdoing by U.S. Democratic presidential candidate Joe Biden or his son."
• June 12, 2019 — Trump tells ABC News he'd welcome foreign help in the 2020 election if offered. “It’s not an interference, they have information — I think I’d take it,” Trump said. “If I thought there was something wrong, I’d go maybe to the FBI — if I thought there was something wrong."

  He added: "It’s called oppo research.”

• Around July 18, 2019 — According to the Washington Post, Trump directed his acting Chief of Staff Mick Mulvaney to delay Congress's allocation of $400 million of military funds for Ukraine. It said this request was made "at least a week" before Trump's July 25 phone call with Zelensky, noted below. The report also said that officials were told to tell Congress the stalling was because of an "interagency process," rather than a direct request from the president.
• July 22, 2019 — BuzzFeed News publishes an investigative article revealing that two GOP operatives with ties to Trump, Lev Parnas and Igor Fruman, "gathered repeatedly with top officials in Ukraine and set up meetings for Trump's attorney Rudy Giuliani as they turned up information that could be weaponized in the 2020 presidential race."
• July 25, 2019 — Trump speaks with Zelenksy on the phone. The White House description of the call is brief, saying Trump congratulated the president on his recent victory. Ukraine said Trump was "convinced that the new Ukrainian government will be able to quickly improve image of Ukraine, complete investigation of corruption cases, which inhibited the interaction between Ukraine and the USA,” according to the Associated Press.

  Later, the Wall Street Journal reported that on the phone call, Trump encouraged Zelensky to have Biden's son investigated "about eight times" and to work with Giuliani.

  Trump also later said of the call:

  The conversation I had was largely congratulatory, was largely corruption, all of the corruption taking place, was largely the fact that we don’t want our people like Vice President Joe Biden and his son creating to the corruption already in Ukraine. 

• Aug. 12, 2019 — A whistleblower complaint goes to the intelligence community inspector general, which then determines the allegations are "credible" and of "urgent concern." Reports later find that the complaint refers to a "promise" Trump made to a foreign leader.
• Aug. 21, 2019 — The Times reported that, in recent weeks, Giuliani had "spoken on the phone and held an in-person meeting, in Madrid, with a top representative of the new Ukrainian president, encouraging his government to ramp up investigations into two matters of intense interest to Mr. Trump" — including the Biden case.

  Giuliani claimed that he was acting as "a private citizen" but also that he was working "with the knowledge and assistance of the State Department." He claimed he didn't know if  Trump "approved" of or was "aware of" his efforts.

• Aug. 28, 2019 — Politico reveals that the aid to Ukraine has been delayed by the Trump administration, triggering bipartisan concern in Congress.
• Sept. 5, 2019 — The Washington Post editorial board reports a reliable source claimed that by withholding aid from Ukraine, Trump "is attempting to force [Ukrainian President Volodymyr Zelensky] to intervene in the 2020 U.S. presidential election by launching an investigation of the leading Democratic candidate, Joe Biden. Mr. Trump is not just soliciting Ukraine’s help with his presidential campaign; he is using U.S. military aid the country desperately needs in an attempt to extort it."
• Sept. 9, 2019 — The House of Representatives announces a “wide-ranging investigation into reported efforts by Trump, his personal lawyer Rudy Giuliani, and possibly others to pressure Ukraine to help the President’s reelection campaign.”
• Sept. 12, 2019 — The Trump administration, under pressure from Congress, releases the $250 million in aid to Ukraine, along with an additional $142 million from the State Department.
• Sept. 13, 2019 — House Intelligence Committee Chair Adam Schiff (D-NY) demands that Director of National Intelligence Joseph Maguire turn over the whistleblower complaint to Congress, in accordance with the law. Maguire refuses after having consulted with the Justice Department. Schiff issues a subpoena for the materials.
• Sept. 15, 2019 — Schiff goes public about the Trump administration withholding the whistleblower complaint.
• Sept. 19, 2019 — Giuliani, speaking about the controversy on CNN, contradicts himself, saying both that he had asked Ukrainian officials to investigate Biden and that he hadn't.
• Sept. 23, 2019 — Sen. Chris Murphy (D-CT) reveals that Ukrainian officials told him in "early September" that Zelensky's administration was concerned Trump was cutting off aid as "a consequence for their unwillingness, at the time, to investigate the Bidens."
• Sept. 24, 2019 — House Speaker Nancy Pelosi announced an "official impeachment inquiry" into Trump's conduct, saying: "This week, the president has admitted to asking the president of Ukraine to take actions that would benefit him politically. The actions of the Trump presidency reveal the dishonorable fact of the president's betrayal of his oath of office, betrayal of our national security, and betrayal of the integrity of our elections."