These sentences demonstrate that the judiciary is responding to calls from elected officials to end the ongoing insecurity and instability in Iran for reasons of public safety. It's clear that the US is implicated in these protests and the Iranian people are paying the price. Such a forceful response to violent, illegal acts will help secure the situation.
Iran is one of the world's leading executioners — it's cementing that reputation with the news that civilians will be sentenced to death for demonstrating against its regime. Authoritarian clerics are threatened by continued protests against the existing patriarchal system and, by resorting to capital punishment, they've shown their fear of the genuine threat the unrest poses to the current draconian system.