The Department of Justice Inspector General is adding to his list of grievances about his office being obstructed by a law enforcement agency—this time, America’s top drug cops.

Michael Horowitz, testifying before the House Oversight and Government Reform Committee on Tuesday, told a familiar story about his inspectors being stonewalled, and denied access to records crucial to their investigations.

The complaints come on top of prior lamentations about the FBI engaging in similar practices, and mostly pertain to allegations of sexual misconduct by federal agents from the ATF, the US Marshall’s Service, and the DEA—the subject of a March report put out by Horowitz’s office.

The investigation detailed allegations about agents’ inappropriate sex solicitation and partying, an assault on a sex worker, and the acceptance of gifts by officials from drug cartels they were charged with investigating

But despite the serious nature of the charges, the probe is incomplete thanks to the Obama administration’s efforts—or lack thereof.

“The failures of the DEA and the FBI to promptly provide all the information we requested impeded our review of the handling of allegations of sexual misconduct,” Horowitz told lawmakers on Tuesday.

He added that both agencies “raised baseless objections” to handing over records to the OIG, despite being clearly compelled to by the law.

“We also determined that the DEA initially withheld from us relevant information regarding an open case involving overseas prostitution,” Horowitz said, noting that his office learned that individuals at the agency who were interviewed by the IG were less than forthcoming and admitted that they were instructed by the DEA “not to talk.”

“Hiding information from the inspector general is simply and totally unacceptable,” Rep. Jason Chaffetz (R-Utah), the committee’s chairman, said during the hearing.

“Your job is to allow the inspector general to get in there and get his fingernails dirty and go figure out the truth. But that’ snot what happened,” Rep. Chaffetz added, speaking directly to one of Horowitz’s fellow witnesses, DEA Administrator Michelle Leonhart.

Leonhart attempted to defend her agency’s record, describing her and Horowitz as having “a very good working relationship.”

“If there’s something that he wants, he has not hesitated to pick up the phone and talk to me about it, and we’ll work it out,” she told lawmakers.

Horowitz responded by saying he’s had to call too much.

“My staff shouldn’t have to spend four months going back and forth,” he said, “I shouldn’t have to be engaging with the highest levels at the FBI and the DEA to get the access.”

He noted that other agencies like the ATF and the US Marshall’s Service handed over the material “immediately.”

“We had no delays. What took us four, five months to get from DEA, we got in a matter of weeks from the ATF and Marshall’s Service,” Horowitz testified.

The DOJ Inspector General has in recent months publicly expressed frustration with the access to information it’s being granted in its bid to conduct oversight.

In February, Horowitz testified in front of Congress, alleging that the FBI was obstructing a number of probes on matters including whistleblower retaliation, and said the bureau was withholding documents related to electronic surveillance, grand jury records, and Fair Credit Reporting Act information.