(CBS News) — Ronny Jackson, President Trump’s embattled pick to run the Department of Veterans Affairs, allegedly provided a large supply of pain pills to a White House Military Office staffer, wrote his own prescriptions, and drunkenly crashed a government vehicle, according to a summary of unverified accusations compiled by Democrats on the Senate Veterans’ Affairs Committee.

The new accusations are more specific than previous allegations, which said Jackson handed out sleeping pills on trips, was known to drink in excess and created a hostile work environment. If verified, these accusations could pose more serious problems for the administration, even as Mr. Trump and the White House have thrown their full support behind Jackson. White House press secretary Sarah Huckabee Sanders said Wednesday that Jackson has undergone four separate background investigations, and no one raised a flag about him. The most recent of these investigations was completed during the Trump administration.

The minority summary is difficult to reconcile with the effusive praise Jackson received from not only President Trump, but also then-President Obama, who gave him the highest rating available and enthusiastically recommended him for promotion. “ABSOLUTELY THE BEST! PROMOTE TO FLAG IMMEDIATELY,” Obama’s evaluation said in 2015. He even included a handwritten note that read, “Ronny’s positive impact cannot be overstated. He is a tremendous asset to the entire White House team. Already at a level of performance and responsibility that exceeds his current rank, promote to Rear Admiral now.”

In 2014, he called him a “key member of my staff,” and wrote of Jackson, “I consider this consummate professional a national asset.” In 2016, Obama again praised Jackson and recommended, “Continue to promote ahead of peers.”

The White House did not immediately reply to CBS News’ request for comment about the allegations.

Jackson was described as, among other things, being “flat-out unethical,” according to the Democrats’ summary.

The summary also claims that missing Percocet pain tablets once threw the White House Military Office “into a panic.” Mr. Trump has taken a hard-line stance against opioids and doctors who overprescribe them.

“It turned out Jackson had provided a large supply to a White House Military Office (WHMO) staffer,” the report summary claims.

Another line in the report summary said a nurse “noted that Jackson wrote himself scripts. When caught, he had someone else, “his physician’s assistant, do it.”

The report summary also claims Jackson was drunk while he was on duty and in charge of the president’s medical bag.

“On at least one occasion, Dr. Jackson could not be reached when needed because he was passed out drunk in his hotel room,” the summary claims.

Once, at a Secret Service going away party, “Jackson got drunk and wrecked a government vehicle.” The report summary doesn’t elaborate on this further, but Jackson disputed the claim Wednesday afternoon, saying that he “never wrecked a car” according to the Associated Press.

In light of the new information, the Veterans’ Affairs Committee delayed Jackson’s confirmation hearing, which was to be held Wednesday.

Democrats on the Veterans’ Affairs Committee provided reporters with some of the unproven allegations made against Jackson by almost two dozen of his former and current colleagues. It can be read here.

— Kathryn Watson; Ed O’Keefe, Major Garrett and Jacqueline Alemany contributed to this report.

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