What is the FCC equal time rule at center of Colbert-Talarico interview controversy?

The broadcasting policy forced Stephen Colbert to post his interview with the Texas Democrat on YouTube instead of airing it on CBS.
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A teacher who ‘made you feel like you mattered’ was killed near her school after a man fleeing ICE crashed a car into hers

What was supposed to be a quiet studentless staff planning day for teachers at a Georgia public school turned into a day of mourning when a man fleeing ...