A February 2016 bipartisan letter signed by several Republican senators that urged then-Ukrainian President Petro Poroshenko to "press ahead with urgent reforms to the Prosecutor General's office and judiciary."
The 2016 letter was signed by Republican Sens. Rob Portman, Mark Kirk and Ron Johnson, as well as Democratic Sens. Dick Durbin, Jeanne Shaheen, Chris Murphy, Sherrod Brown, and Richard Blumenthal.
[Senator Ron Johnson later signed onto a letter with Iowa Sen. Chuck Grassley to then Attorney General Bill Barr asking him to investigate, in part, the allegations surrounding Biden and Ukraine.]
At a hearing in March 2016 on Ukrainian reforms, Tennessee Sen. Bob Corker raised concerns about corruption in Ukraine and said his hearing would delve into what pressure the U.S. could apply.
At the same hearing, John E. Herbst, a former Ambassador to Ukraine in the Bush administration and later, director of the Atlantic Council's Eurasia Center, testified that there was widespread support for the removal of Sholkin and praised specifically praised Biden.
Ukraine's legislature voted to fire Shokin in March 2016.