Look, I'm not a lawyer and so there might be subleties that would prevent this, but in terms of punishing Carr, couldn't the state just kill all his children?
God and God alone reserves the right to curse a lineage to the 3rd and 4th generations; He specifically commands us NOT to do this: "The son shall not die for the sin of the father, neither shall the father die for the sin of the son, but let every man die for his OWN sin."
Besides, if we punish the kids for the father's crime, we lose all moral high ground in the fight against reparations.
Still, though, it's a d@#% shame that those victims all died without children, and Carr has already spawned. There's a basic genetic unfairness there. Maybe the survivor, H.G., will compensate by marrying a homeschooling patriarch and having 14 kids in revenge for her friends' extinction.
Mr. Carr probably cares very little about his progeny (no doubt they were "accidents"). I'd imagine he'd think you were doing him a favor.