The battle of words between the Director of the Central Intelligence Agency and the chairwoman of the Senate committee whose charge is to oversee the CIA's activities is primed to erupt into a Constitutional crisis, and possibly a watershed moment for the public conversation over the powers of the U.S. Government's spying apparatus.

On Tuesday, senior Senator Dianne Feinstein, who has been an outspoken supporter of the surveillance programs of the National Security Agency, took what was a private intra-government dispute to the Senate floor, and its television cameras. In a long and blistering speech, the Senate Intelligence Committee Chairwoman spoke publicly about the alleged spying by the CIA on the computers, networks, and members of the Senate Intelligence Committee.

In so many unprecedented, public words, Feinstein accused CIA John Brennan, and the agency he heads, of illegally spying on Congress in an effort to contain documents relating to the CIA's Detention and Interrogation Program (referred to as the Internal Panetta Review), which Feinstein's committee has been investigating -- or at least trying to investigate -- for years.

Feinstein's speech included several serious charges leveled against Brennan and the CIA, and raised the implications of the agency's alleged shattering of the Constitutional separation of powers between the Executive and Legislative branches. The speech also exposed what appears to have been a longstanding game of bait-and-switch between her committee and the agency it's constitutionally mandated to oversee.

Here are some excerpts of Feinstein's more devastating allegations from her Senate speech:

"On January 15, 2014, CIA Director Brennan requested an emergency meeting to inform me and Vice Chairman Chambliss that without prior notification or approval, CIA personnel had conducted a "search" - that was John Brennan's word - of the committee computers at the offsite facility. This search involved not only a search of documents provided to the committee by the CIA, but also a search of the "stand alone" and "walled-off" committee network drive containing the committee's own internal work product and communications.

"According to Brennan, the computer search was conducted in response to indications that some members of the committee staff might already have had access to the Internal Panetta Review. The CIA did not ask the committee or its staff if the committee had access to the Internal Review, or how we obtained it. Instead, the CIA just went and searched the committee's computers.

"In place of asking any questions, the CIA's unauthorized search of the committee computers was followed by an allegation - which we now have seen repeated anonymously in the press - that the committee staff had somehow obtained the document through unauthorized or criminal means.

Feinstein then brought up sobering concerns about the implications of the CIA's accused actions.

"I have grave concerns that the CIA's search may well have violated the separation of powers principles embodied in the United States Constitution, including the speech and debate clause. It may have undermined the constitutional framework essential to effective congressional oversight of intelligence activities or any other government function.

"The CIA's search may also have violated the Fourth Amendment, the Computer Fraud and Abuse Act as well as Executive Order 120003, which prohibits the CIA from conducting domestic searches or surveillance."

The full speech is available for viewing here, and is highly recommended viewing.

In a prescheduled speech at the Council on Foreign Relations the same day, Brennen denied Feinstein's allegations, saying, "Nothing could be further from the truth ... We wouldn't do that. I mean, that's just beyond the scope of reason."

Reserving judgment until the facts are in on what appears to be a longstanding showdown between the CIA allegedly obstructing the intelligence committee's investigation into torture, top Senators spoke of their concerns on the matter, according to NPR. "If what they're saying is true about the CIA, this is Richard Nixon stuff," said Republican Sen. Lindsey Graham. "This is dangerous to a democracy. Heads should roll. People should go to jail, if it's true. The legislative branch should declare war on the CIA, if it's true." "It's very disturbing," said Sen. John McCain. "There needs to be a thorough and complete investigation."

Meanwhile, Edwards Snowden, ex-NSA contractor who leaked documents detailing a plethora of NSA spying programs, told NBC News in a statement that Feinstein's outrage and concern for the Fourth Amendment, while pointing to a serious Constitutional concern, was hypocritical:

"It's clear the CIA was trying to play 'keep away' with documents relevant to an investigation by their overseers in Congress, and that's a serious constitutional concern," said Snowden to NBC News. "But it's equally if not more concerning that we're seeing another 'Merkel Effect,' where an elected official does not care at all that the rights of millions of ordinary citizens are violated by our spies, but suddenly it's a scandal when a politician finds out the same thing happens to them."