Untrue. Though not terribly far off.
Here's a 1946 incident.
http://en.wikipedia.org/wiki/1946_Georgia_lynching
One of the problems is definition. Not all murder are lynchings. To my mind lynching implies a semi-public nature of the event, which is more or less the point, to terrify a segment of the community.
Emmett Till was from the mid-50s and is sometimes called a lynching, but it was a secretive crime, not a lynching to my mind.
Then the George Zimmerman trial and the Duke lacrosse charges were a form of lynching.