I strongly suspect that Barack Obama was told “You lie!”, because he was lying, has lied, and will lie again.
The Lie was obvious to even the most casual observer. Maybe he just wasn’t suppose say verbally what everyone was thinking.
Obama had JUST called Republican critics “liars” in his speech.
Barack went before Congress so he could get Democrat applause on the key lines. That opened him up to counter response.
The Democrats were SILENT when a Code Pinko heckled John McCain at the GOP Convention in 2008 DURING his Presidential nomination acceptance speech.