BOSTON (CBS) - As someone who produces a lot of political coverage for radio and TV, it is virtually impossible to totally exclude partisans from the conversation. Sometimes the best you can do is make sure it's balanced, as WBZ NewsRadio 1030 does with its virtual roundtable.

But during this election, CNN – the network that almost created partisan rhetoric back in the 1980s with "Crossfire" – has gone way overboard by featuring entire panels of flagrant partisans in its election coverage.

I know you've seen them, mixed in with the actual reporters and some analysts – like former Obama aide David Axelrod and conservative commentator S.E. Cupp – who are knowledgeable and make an honest effort to transcend their own partisan leanings.

Perhaps CNN's most notorious offense has been paying former Trump campaign manager Corey Lewandowski to ostensibly provide "insight" into that campaign while he remained on the Trump payroll and offered nothing beyond the most rote pro-Trump spin.

But the Donna Brazile fiasco isn't any better.

She is the longtime Democratic operative who we now know – thanks to emails illegally obtained by Wikileaks - was actively meddling in the Democratic primary on behalf of Hillary Clinton, by feeding her debate audience questions in advance.

CNN has now cut ties with Brazile, but they never should have had any in the first place.

They employ enough actual journalists to get all the analysis they want without it being tainted.

Let's hope that is a lesson now learned.

Listen to Jon's commentary: