WASHINGTON – Sen. Cory Booker challenged his colleagues to try to expel him for breaking rules he opposes Thursday after promising to release an email including comments by Judge Brett Kavanaugh about racial profiling that had been deemed confidential.

"I’m going to release the email about racial profiling," Booker said at the start of the third day of Kavanaugh's confirmation hearings in the Senate Judiciary Committee. "I understand the penalty comes with potential ousting from the Senate."

The documents had been cleared for the release by the time they were issued, but Booker admitted to reporters that violated committee rules when he read from several emails while questioning Kavanaugh on Wednesday night.

Booker had quoted from a 2002 document that he said showed Kavanaugh as an aide to President George W. Bush entertaining the use of racial profiling to combat terrorism after 9/11.

Kavanaugh asked to see the email, but Booker said he wanted to focus on Kavanaugh's views about profiling on Thursday, not then. Sen. Mike Lee, R-Utah, then objected, saying Booker was citing an email that had been deemed confidential by the committee and it was unfair to question a witness about a document he could not see.

Booker said there was no reason for the email to be deemed confidential because it did not involve national security.

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The cache of emails released by Booker’s office includes several with the subject line “racial profiling” and many date to January 2002 as the Bush administration struggled to define exactly how and who could be subjected to searches at airports in the wake of the 9/11 terror attacks.

At the time, Kavanaugh was part of the team of Bush lawyers working with the Justice Department on the legality of those searches. In some of the documents released by Booker, the lawyers are questioning whether they should create a “race-neutral system at all” or use race in some circumstances as a factor to decide who gets searched.

Kavanaugh writes in one email that he and others favor “effective security measures that are race neutral” but need to decide how to deal with such measures while searches are being conducted before comprehensive standards are determined.

As the committee resumed hearings Thursday, Chairman Charles Grassley, R-Iowa, said his staff had been working until 3 a.m. with the Justice Department to get documents senators wanted to use at the hearing cleared for public release.

He said he had urged senators to request documents in August to have time to go through the process.

Booker countered that the process Grassley was citing showed the process of producing documents for the hearing was a sham, and he would have his staff release the letter anyway, knowing it violated Senate rules.

"I broke the rules yesterday," Booker told reporters outside the hearing room. "Today because I shamed them ... they quickly moved to release documents that I was talking about. Yesterday, I broke the sham 'committee confidential' rules and I accept full responsibility for what I'm doing. Whatever the consequences are, here I stand."

He argued that his actions were justified because Kavanaugh would have a lifetime appointment and his record on critical issues, including abortion, affirmative action and torture were being shielded from scrutiny by the confidentiality rules.

In response to Booker in the hearing, Sen. John Cornyn, R-Texas, said making the emails public was akin to a senator releasing classified information because the senator disagreed with the classification.

"No senator deserves to sit on this committee or in the Senate itself if they decide to be the law unto themselves," Cornyn said. "Running for president is no excuse for violating the rules of the Senate."

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Democrats on the committee then spoke out against the classification process. Sen. Dick Durbin, D-Ill, urged fellow Democrats to join Booker.

"If there's going to be some retribution against the senator from New Jersey, count me in," Durbin said.

Booker later challenged Cornyn to seek to punish him.

"If he feels that I and now my fellow colleagues violated the rules, then bring the charges," Booker said. "I'm ready to accept full responsibility for what I’ve done ... and stand by public's right to have access to this document."

Expulsion of senators, the most severe penalty the chamber can impose on a member, requires a two-thirds vote, meaning Booker's fellow Democrats would have to join with the Republican majority for it to happen. Other penalties including public and private reprimands or a public vote of censure.

Booker's fellow Democrat from New Jersey, Bob Menendez, received a "public letter of admonishment" earlier this year for violating senate gift rules and advocating for the personal and business interests of the donor who gave the undisclosed gifts.