Backstabbing

Sometimes, you got to stab someone in the back. Really, it happens. Part of the profession, backstabbing.
Most critters have a soft belly, or gooy eyes, or even weak ankles. My kind don't have any of those weaknesses. Instead, we've got this one itty-bitty spot at the small of our backs, right between the ridged raised plates of our exoskeletons, that remains hatchling-soft.
That soft spot acts as an escape route for our micro-selves, the secondary form that all of my kind have, but only use when our primary form is near death.
If the mirco-self can escape, it'll eventually grow into a new primary form, with most of our previous primary form's memories. It'll even eventually grow its own micro-self, and thus be safe from true death.
But if someone stabs you in just that spot, they'll kill your micro-self.
And each primary form can only create one micro-self.
In my profession, we seek out those who pose a danger to society, who purposefully destroy the micro-selves of innocents, or otherwise break the most important of our laws. We seek them out, and take them in for judgement.
And if they're found to be guilty of the same crimes for over three primary forms, or found to willfully destroy the micro-self of another, we sentance them to backstabbing.
It isn't always easy to stab someone in the back, but that is part of the job.
Doesn't make it any easier, though.