The Justice Department gave Hunter Biden “preferential treatment” during an investigation into his failure to pay taxes, according to an IRS whistleblower who said prosecutors blocked search warrants, slow-walked the probe and shut down pursuit of leads, including ones that related to President Biden.

Gary A. Shapley Jr. said he’d never seen an investigation handled that way during his 14 years as a criminal investigator with the IRS.

He said every time there was a conflict or decision to be made in the investigation into Hunter Biden, federal prosecutors ruled in ways that benefitted Mr. Biden.

“I am alleging, with evidence, that DOJ provided preferential treatment, slow-walked the investigation, did nothing to avoid obvious conflicts of interest in this investigation,” Mr. Shapley told the House Ways and Means Committee in testimony last month.

The committee voted Thursday to release the testimony publicly, waiving a section of federal law that generally shields private taxpayer information.

“The American people deserve to know that when it comes to criminal enforcement, they are not on the same playing field as the wealthy and politically connected class,” said committee Chairman Jason Smith, Missouri Republican. “The preferential treatment Hunter Biden received would never have been granted to ordinary Americans.”

A second whistleblower, identified as “Mr. X” in committee documents, was Mr. Shapley’s subordinate. He said the Justice Department’s handling of Hunter Biden “has honestly been appalling.”

“Looking back on everything, they had the best investigators in the nation and the prosecutors were the JV squad and weren’t up to the task of handling such a big case,” he said. “They would often slow-walk investigative steps, often not follow the appropriate investigative procedure, and would say that we couldn’t do or had to wait on certain steps because there were too many approvals in front of us.”

Mr. X said he began investigating Hunter Biden as far back as 2018, when bank reports suggested he had paid prostitutes and was living lavishly, in what investigators saw as red flags for tax problems.

Mr. Shapley said he joined the probe in January 2020, after the FBI had obtained Hunter Biden’s laptop and spotted what it thought could be evidence of tax problems.

The IRS began its probe, and Mr. Shapley said they developed an investigative plan with interviews and search warrants, but those plans were derailed by the Justice Department.

Mr. Shapley said he was pulled off the probe last month, after his whistleblower communications with Congress.

The Justice Department’s investigation was run by the U.S. Attorney in Delaware, David Weiss, who was appointed by President Trump and kept on by President Biden, who said he didn’t want to be seen putting his thumb on the case mid-stream.

Hunter Biden has decided to plead guilty to two misdemeanor tax charges and enter a diversionary program for a felony gun charge, in a deal that is expected to shield him from any prison time. The gun charge would be wiped away if he keeps a clean record during two years of probation.

He’s scheduled to appear in federal court in Wilmington on July 26 to enter the plea.

Republicans have blasted the deal, saying others facing those charges would receive jail time.

The Justice Department said Mr. Weiss had free rein to make whatever charging decisions he wanted.

“He needs no further approval to do so,” the department said.

Mr. Weiss’s office declined to comment.

Mr. Shapley said he discovered tax problems for Hunter Biden dating back to 2014 and 2015. He recommended that Hunter Biden be charged with tax evasion in 2014 and failure to file in 2015 by the U.S. attorney in the District of Columbia, Matthew Graves.

Mr. Shapley said Mr. Graves, a Biden appointee, refused.

Mr. Graves’ office suggested it was Mr. Weiss’s call.

“U.S. Attorney Weiss was given full authority to bring charges in any jurisdiction he deemed appropriate. He did not need approval from this office or the U.S. Attorney to bring charges in the District of Columbia,” Mr. Graves’ office said.

Mr. Shapley also fueled ongoing questions about a confidential source who told the FBI about a bribery scheme involving the president.

According to former Attorney General William P. Barr, the information was turned over to the Delaware investigation into Hunter Biden. But Mr. Shapley says if that’s true, it was never shared with him, nor with FBI agents working with him.

“This appears to be another example of prosecutors obstructing the investigative process,” Mr. Shapley said in an affidavit given to the committee earlier this month. “It is more likely than not that there are more examples of information that prosecutors concealed from investigators.”

Mr. X, the other whistleblower, also said through his lawyer that he never saw the human source information, even though it could have been relevant to his probe.

Democrats blasted Thursday’s release of the whistleblowers’ testimony.

Rep. Earl Blumenauer, Oregon Democrat, called it “politically charged” and said it weaponized the use of private taxpayer information.

When Democrats controlled the committee they made a similar bid to obtain and release then-President Trump’s tax returns, but Mr. Blumenauer said this was “nothing like” that.

“The American people deserve better,” he said.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.