Schiff: Bolton refused to give sworn statement on Ukraine to House Democrats

What he's saying: ""For whatever reason, [Bolton] apparently was willing to testify before the Senate, but apart from that, seems intent on saving it for his book," Schiff told host Rachel Maddow. "He'll have to answer for that, but at this point we have not made a decision about whether or not to move forward with a subpoena, but it is certainly something that we will be discussing."

Flashback: Bolton said Monday that he would testify in Trump's impeachment trial should the Senate issue a subpoena.

The big picture: The Senate acquitted Trump of abuse of power and obstruction of Congress on Wednesday, with nearly every Republican declining to pursue new information about Trump's Ukraine activities.

Go deeper: Nadler says House Democrats will "likely" subpoena Bolton