Wanting someone who killed in desparation in well-known and very extenuous circumstances a lighter punishment in no way condones the crime.
Many think the justice system should prioritize rehabilitation, not retribution.
Instead of fixing people, retribution just breaks them even further, making it more likely they’ll commit a crime in the future, oftentimes because they’re forced to by circumstances they find themselves in when (if) they’re finally set free.
Rhetoric does mean speech. It’s usually used in a political context, so incediary rhetoric would be incidiary (political) speech.
Other than that, rhetoric is often equated with the policies talked about, so Trump’s rhetoric would be anti-immigrant, anti-abortion, pro-Russia, etc.
As for the ‘it’s not rhetoric’ part of the title - I think they meant it’s not just speech, it’s verifiable - so no direct meaning of ‘lie’ anywhere although the meaning of ‘lie’ is heavily implied.