Google is declining to hand over certain documents and raising concerns about anti-Google bias amid the multistate antitrust investigation into its digital advertising practices, according to a new Wall Street Journal report.

Google lawyers have been pushing back on the scope and scale of some document requests from Texas Attorney General Ken Paxton (R), who has been leading the 48-state investigation, the Journal reported. And Google is continuing to raise concerns about some of the experts that Paxton’s office has tapped to help with the antitrust investigation, pointing out several of those consultants have worked with Google rivals or critics.

A Google spokeswoman said the back-and-forth with Texas over particular documents is a standard part of any legal inquiry. She said Google has had similar discussions about the scope of document requests with regulatory bodies around the world.

“It’s standard practice to discuss the scope of document requests. To date, Texas has requested, and we have provided, over 100,000 pages of information,” a Google spokeswoman said. “We have a strong track record of constructive cooperation with regulators around the world. But we’re also concerned with the irregular way this investigation is proceeding, including unusual arrangements with advisers who work with our competitors and vocal complainants.”

Paxton, meanwhile, told the Journal, “Every indication right now is they don’t believe that they’re clean because they don’t act in any way like they are.”

According to documents reviewed by the Journal, Google has been reluctant to hand over personal communications from executives at the company and private messages among particular Google employees.

A source familiar told The Hill that the team looking into Google in Texas changed over the course of their correspondence, creating delays, and Google is planning to produce more documents on key topics.