Matthew Whitaker’s rise to the top of the U.S. Justice Department on Wednesday came with immediate scrutiny of his past statements, many of which display deep partisanship and unease with the Russia investigation he now oversees.

A former U.S. attorney in Iowa, Whitaker ran unsuccessfully for the U.S. Senate in 2014 but never lost his taste for politics. He remained in Republican circles and, last year, emerged on CNN as a critic of the Russia investigation, repeatedly calling for limits to the scope of the special counsel’s probe.