There is a “Jailbreak detected” Fixlet in our MDM Fixlet site. It gives you 3 options:
Notify the user that they are not compliant.
Deprovision the user (selective wipe) to remove all the corporate data/corporate access that you installed through MDM.
Wipe the device to restore it to factory settings.
You can set any of these as a policy (same as any other action in a Fixlet).
You can see the jailbroken devices in web reports (easiest way would just be to look at a report for the jailbreak Fixlet). You will need to use the console (or the self-service portal) to send the wipe command manually or to set up the automatic policy.