MoveOn PAC mailed a flyer to voters in Illinois' 10th District saying that Brad Schneider, who is running in the upcoming Democratic congressional primary, is really a Republican. They cite as proof Federal Election Commission reports showing that Schneider repeatedly contributed to Republicans both in the district he is running in and across the country. His contributions totaled thousands of dollars. The flyer also pointed out that official voting records show that Schneider voted in Republican primaries in two recent elections.
Schneider admits that he contributed to all the Republicans and that he voted in one Republican primary. He says the official voting record is wrong about the other primary. He says, however, that he is not a Republican, and he is saying that people are spreading lies.
It should be noted that Schneider's opponents haven't gone as far as MoveOn PAC has by saying that Schneider is a Republican. None of his opponents has done anything other than point out the facts of Schneider's contributions and primary voting record.
The question, therefore, is whether MoveOn PAC, in saying Schneider is a Republican, was expressing an opinion or was making a statement of fact. If MoveOn PAC was giving its opinion, it wasn't lying. An opinion is just a belief. A lie is an intentional misstatement of fact.
Schneider's assertion that MoveOn PAC is lying seems to be based on the notion that MoveOn PAC is not entitled to have an opinion about whether he is a Republican, and that only he can answer that question.
In one sense, Schneider is correct. He can consider himself to be a Democrat even if he votes for Republicans, contributes to them, and votes in Republican primaries. But that would be like someone considering himself to be Jewish even if he goes to mass and takes communion every Sunday in a Christian church.
Of course, Schneider can think he is acting like a Democrat. But other people are entitled to their opinions, too. Schneider, for example, brands Bob Dold as a Tea Party Republican even though Dold has never said that is what he is. If Schneider is justified in judging Dold based on Dold's voting record, MoveOn PAC can just as legitimately judge Schneider based on how he has behaved.
The biggest clue about whether Democratic voters should believe that Schneider is a Democrat is that Schneider doesn't seem to understand why Democrats are upset that he has been voting for and contributing to Republicans. If he had any real involvement in Democratic campaigns, if he really identified as a Democrat, if he had been supporting Democrats instead of Republicans, he'd know.