Here is what the United States Constitution says about impeachment:

“The House of Representatives ... shall have the sole Power of Impeachment. ...The Senate shall have the sole Power to try all Impeachments. ... And no Person shall be convicted without the Concurrence of two-thirds of the Members present. ... The President, Vice President and all civil Officers of the United States, shall be removed from Office on Impeachment for, and Conviction of, Treason, Bribery, or other high Crimes and Misdemeanors.”

Impeachment is a three-step procedure. First, the Congress (either a House or Senate committee) investigates. Second, the House must pass articles of impeachment. Third, the Senate holds a trial, and if the office-holder is convicted by a two-thirds vote, he or she is removed from office.

There is no requirement that the first stage (investigation) must be public. There is no requirement that the entire House must authorize the investigation. There is no requirement that whistleblowers be identified (in fact that would be illegal).

President Trump and some Republicans are complaining that the investigation now underway is unfair.

“Republicans are totally deprived of their rights in this Impeachment Witch Hunt,” Trump tweeted. “No lawyers, no questions, no transparency!”

One of the commentators for Fox News explained recently why Trump is wrong about this. Andrew Napolitano was a judge in New Jersey who has written nine books on legal and political subjects, and who now works as an analyst for Fox News. He said: “This (investigation) is not a trial. This is the prosecutors interviewing their witnesses, and that procedure never takes place in public because you want privacy and you want candor.”

He explained that the investigation phase is necessary for lawmakers to determine whether there is actually a firm case to bring against the president. The House members also need to decide which information should be brought forward publicly to formally make the case for impeachment. The process “is consistent with the Constitution and consistent with the House rules," he said.

Napolitano also wrote an op-ed in which he said that “impeachment is always constitutional if it originates in the House and if its basis is arguably for treason, bribery or other high crimes and misdemeanors.”

He concluded that “The president refused to deliver congressionally authorized and ordered military and financial aid to an ally [Ukraine] threatened with Russian invasion until the ally’s government performed a presidentially requested favor for his re-election campaign – a favor that is unlawful to ask for.”

Last month, an even more important opinion was issued by Chief Judge Beryl Howell of the Federal District Court in Washington. In a 75-page ruling, she decided that the impeachment investigation is legal, and the House Judiciary Committee is entitled to view secret grand jury evidence gathered by the special counsel, Robert S. Mueller.

In a rebuke to the Trump administration, she wrote that the White House strategy to stonewall the House makes the grand jury evidence even more relevant to an impeachment inquiry. She cited Mr. Trump’s vow to fight “all” congressional subpoenas and an extraordinary directive by his attorney that executive branch officials should not provide testimony or documents to impeachment investigators.

“Congress’s need to access grand jury material relevant to potential impeachable conduct by a president is heightened when the executive branch willfully obstructs channels for accessing other relevant evidence”, Judge Howell wrote.

Her ruling is similar to court decisions in 1974 that permitted Congress to see secret grand jury evidence as they were deciding whether to impeach President Richard Nixon.

Judge Howell’s decision that House Democrats are legally engaged in an impeachment inquiry certainly undercuts President Trump’s arguments that the investigation is a sham. He tweeted that “the Radical Left Dems have No Case. It is all based on their Fraud and Fabrication!”

The federal court has now destroyed Trump’s argument.

James H. Manahan is a Harvard Law School graduate and was named one of Minnesota’s Top Ten Attorneys. He now handles family law, wills and probate in the Lake County area, and does mediation everywhere. He writes a regular column on legal issues for the News-Chronicle. He can be reached at jamesmanahan36@gmail.com or jamesmanahan.com.