Matthew Whitaker, Jeff Sessions’ chief of staff who will take over as acting Attorney General with his boss’ ouster, has been an outspoken advocate of limiting — or even ending — the Mueller investigation.

In an August 2017 op-ed published on the CNN website, the former federal prosecutor argued that Mueller had come “dangerously close” to crossing a “red line” in the investigation by looking at Trump’s personal finances and those of his business.

“It does not take a lawyer or even a former federal prosecutor like myself to conclude that investigating Donald Trump’s finances or his family’s finances falls completely outside of the realm of his 2016 campaign and allegations that the campaign coordinated with the Russian government or anyone else,” Whitaker wrote. “That goes beyond the scope of the appointment of the special counsel.”

Whitaker added in the piece that “it is time for [Rod] Rosenstein…to order Mueller to limit the scope of his investigation.”

It appeared to be part of a summer 2017 campaign by Whitaker — then reportedly on the shortlist to replace Don McGahn as White House counsel — to portray himself as a hardliner on the Mueller probe.

In June 2017, Whitaker appeared on a CNN panel on the Mueller probe.

“What will get Republicans worked up is if we have a Department of Justice in chaos,” Whitaker said on the panel. “We’ve already heard rumors on the wind about Sessions’ tenure, so suddenly we could have a President that understands that if I control the Department of Justice, I control this investigation.”

Whitaker also had an active Twitter presence, at times indicating sympathy with those calling for an end to the investigation.

The acting attorney general specifically sympathized with the plight of former Trump campaign chairman and Svengali to Ukrainian oligarchs Paul Manafort. After the FBI conducted a dawn raid on Manafort’s Alexandria condo, Whitaker asked rhetorically “Do we want our Gov’t to ‘intimidate us? Hmm.”

Do we want our Gov't to "intimidate" us? Hmm -FBI's Manafort raid incl. a dozen agents, 'designed to intimidate,' | https://t.co/KAHQq26q2M — Matt Whitaker 🇺🇸 (@MattWhitaker46) August 25, 2017

In another tweet, Whitaker appears to suggest a way of keeping Mueller’s findings under wraps indefinitely. The following tweet could open up a path to sealing any report that Mueller prepares relying on grand jury evidence from the public.

Article is correct, it will be very difficult to ever see evidence discovered by #Mueller grand jury investigation https://t.co/aNKBmi5xI2 — Matt Whitaker 🇺🇸 (@MattWhitaker46) August 17, 2017

Whitaker also took a hard line against supposed “leakers” informing the press about details in the Russia probe.