The focus on Shaffer also comes as sources tell CNN that the Justice Department summoned Trump voters this week to Georgia, Michigan and Pennsylvania – all states lost by former President Donald Trump. The Justice Department is scrutinizing the use of so-called alternate voters by the Trump campaign. The new round of summonses represents an escalation of a criminal investigation that, so far, has approached lower-level Republicans. Throughout, however, federal investigators have been searching for information on senior politicians, including at the top of the Trump campaign. In the weeks leading up to the 2020 election and until January 6, 2021, Trump’s allies sent fake voter placards to the National Archives stating that the then President had won seven states he had actually lost. The bid failed and then-Vice President Mike Pence confirmed Joe Biden’s election victory on January 6, after the rioters were cleared from the US Capitol. Just this week, a separate inquiry by the House Select Committee highlighted that some lawyers working with Trump’s campaign had directed efforts to bring Trump’s fake plaques to lost battlefield states. CNN previously reported that the criminal investigation had sought information from Republicans in several states, including Georgia and Michigan, who had resigned from Trump’s election. In this last round of calls, the targets are people who signed illegal lists, sources say. Shafer did not respond to a request for comment. He is now embroiled in three separate investigations – the Jan. 6 congressional inquiry, a Georgia Fulton county, the criminal investigation, and the Justice Department investigation. Another source said the FBI had leaked information, including the contents of a telephone, to Brad Carver, one of Georgia’s fake voters. The FBI has also sought information about the Republicans of Georgia who took part in a private Signal interview ahead of the 2020 election, the source said. Carver did not respond to a request for comment. This story has been updated with additional details.