The robot is likely to have a constant internet connection so it could just call the police.

Alternatively they could add a chain gun to the robot to deal with the vandals

But who is going to pay for all that ammo? That sounds expensive to the tax payer and not ideal for re-election. Perhaps you could employ the robots in ammo factories first to bring the cost of ammunition down and then the frequent use on the lower cla.., I mean criminals, wouldn’t be so costly.

>add a chain gun to the robot to deal with the vandals

Asimov reeling in his grave.