1. 1968 Supreme Court case of Epperson v. Arkansas
Comment #185844 by smithsb on May 28, 2008 at 7:37 pm
C-SPAN didn't start using separate phone numbers for different party affiliations until the Monica Lewinski situation developed in the 90s, when the number of anti-Clinton callers was way out of proportion to what was reflected in national polls. So the separate phone lines enforce a reasonable balance that would be difficult to achieve if one partisan group decided to launch an assault on the phone lines. Note that these are not toll-free phone numbers. Note also that C-SPAN hosts remain as neutral as possible--but they also leave it up to the callers to ask questions that are almost always more penetrating than anything one is likely to hear on CNN or MSNBC.
Shawn Smith