(CBS) — In a hearing on the Environmental Protection Agency’s budget, Scott Pruitt spent much of his testimony on Thursday before the House Energy and Environment Subcommittee defending himself against a string of ethics controversies that have prompted calls for his ouster. Pruitt said he has “nothing to hide” as it relates to how he runs the agency.

“Facts are facts and fiction is fiction, and a lie doesn’t become truth just because it appears on the front page of the newspaper. Much of what has been targeted toward me and my team has been half-truth, or at best stories so twisted they do not resemble reality,” said Pruitt.

He added, “Those who attack the EPA and me are doing so because they want to attack and derail the president’s agenda and this administration’s priorities, I’m simply not going to let that happen.”

Democrats, however, were unimpressed with Pruitt’s defense. The ranking Democrat on the committee, Rep. Paul Tonko, of New York, told Pruitt he had “failed as a steward of the environment” and has a tendency to “abuse” his position for “personal gain.

“Your conduct as administrator has demonstrated a lack of respect for American taxpayers,” Tonko added, slamming Pruitt on his lack on transparency, lack of contrition and fitness for the job at EPA.

Democratic Rep. Frank Pallone of New Jersey said Pruitt has brought “secrecy” and “scandal” to the EPA, suggesting that in any other administration, Republican or Democrat, Pruitt would have been “long gone” by now as administrator.

“I am confident that these investigations will affirm what I have come to believe is true: you are unfit to hold public office and undeserving of the public trust,” added Pallone.

Some Republicans, however, came to Pruitt’s defense. Rep. McKinley said that Democratic lawmakers were “ignoring the progress that’s been made” at the EPA instead were “grandstanding” at Thursday’s hearing, calling it a “classic display of innuendo and McCarthyism” when pressing Pruitt about his ethics.

While Pruitt spent most of the hearing sidestepping criticism of his leadership at EPA, at one point he conceded he did have some knowledge of big pay raises awarded to two close aides.

At the hearing, Rep. Tonko pressed Pruitt on whether he knew about the raises for 30-year-old senior legal counsel Sarah Greenwalt and 26-year-old scheduling director Millian Hupp. In a Fox News interview on April 4, Pruitt insisted he didn’t approve the raises and didn’t know who did.

Documents later showed EPA chief of staff Ryan Jackson signed off on the raises and indicated he had Pruitt’s consent.

Pruitt said Thursday he actually delegated authority to Jackson to give the raises but didn’t know the exact amounts and wasn’t aware of the process. Tonko responded to Pruitt: “I’m concerned that you have no idea what is going on in your name at your agency.”

Greenwalt received raises of more than $66,000, bringing her salary to $164,200. Hupp saw her salary jump to $114,590, after raises of more than $48,000.

Pruitt also denied having ever approved the installation of a phone booth in his office, which cost the agency $43,000. Pruitt instead blamed career staff at the EPAa for signing off on the purchase.

“I was not involved in the approval process, and if I had known about it, I would have refused it,” said Pruitt.

Despite the questions that have been raised about Pruitt’s ethical practices, President Trump has defended Pruitt as doing a “fantastic job” at the EPA and expressed confidence in on at the agency.

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