Pichai is scheduled to appear before a committee of the US House of Representatives, where he will likely face Republican questions about the search engine giant's bias or unwillingness toward conservative users.
In a statement, House Majority Leader Kevin McCarthy cited anonymous information suggesting that Google "may not exercise its vast power impartially". McCarthy added, without citing any evidence, that Google's "business practices may have been affected by political biases".
A Google representative declined to comment on Pichai's next testimony.
The House Judiciary Committee, chaired by Republican Bob Goodlatte, held hearings throughout the year to determine whether technology giants were biased against the Conservatives. Twitter CEO Jack Dorsey was the last major technology figure to appear before the committee at a hearing in September.
Google had previously refused to make Pichai available for a hearing before the Senate Intelligence Committee, even though Dorsey and Facebook operations managers, Sheryl Sandberg, were present.