When it comes to lying, everyone has a "tell".  Some subtle gesture that gives that person away.    
A slow blink. A slight finger tap. A barely discernible furrowed brow.  
So what's John McCain's tell?  Talking.  
Watch him very closely the next time he's at a campaign rally, or when he's being interviewed.   As soon as he opens his mouth to speak, that's the tell.  He may hesitate slightly, with mouth agape, as if to rethink the order of words, but it's too late. 
He's already activated the launch sequence of a complete fabrication.  

Remember, keep your eye on the opening of his mouth. You should be able to pick up on this your first try.  
Now cultural anthropologists and those who study sociopaths will tell you that no two tells are alike. Not even in the animal kingdom.  But recent observations of the McCain campaign may disprove that theory.  
In one study, respondents were each given a short video clip of different McCain spokespersons and asked to determine if there was any dissembling behavior.  And if so, they were to write down what they thought  gave it away.  
To establish a baseline, the first video was of a gorilla being truthful about wanting to kill a former research assistant that worked here for years.   
The respondents all answered correctly;  the gorilla was being honest. 
Then they watched the other videos and they were asked to fill out a multiple choice questionnaire that indicated "most likely lying, possibly lying, not sure, etc.  
The results were startling.  

Respondents who watched videos of Rick Davis, Steve Schmidt and Tucker Bounds all checked the same answer on the questionnaire.  "E"-- lying through the skin of their teeth.  
After asking each respondent what the different "tells" were for each of the McCain spokespersons, they all said it was when each started talking--that was the dead giveaway.  
We're taking a survey.  
Have you noticed the "tell" of the McCain campaign?