First, you may want to differentiate between the scenario where your organization is targeted directly, and the one where it is indirectly affected by the situation unfolding in its vicinity. The first case arguably holds more potential to turn violent and exceptionally dangerous, but the other also can have serious consequences. At the very least, a demonstration could prevent employees from leaving and accessing the facility. An even more serious scenario would involve the crowd gaining access to the facility/office and causing harm to employees and property, or leading to the loss of sensitive information.
Monitoring the situation around your area and reviewing available data might be a good place to start. Then, you might want to ask yourself some questions:
Are the protests and demonstrations common?
Do they often turn violent?
Is there a football stadium or other crowd-gathering places nearby?
Moreover, are the political tensions high?
Is local law enforcement efficient?
Answering those questions can help you estimate the probability of a dangerous case of civil unrest unfolding in your area. Then, good perimeter security, careful monitoring and regulated access to the facility are crucial to ensuring safety.
Lockdown and evacuation procedures should also be among the countermeasures. Moreover, a warning procedure and providing alternative entrances and exits can play a big part. Above all, if possible, this planning should be conducted in close collaboration with local authorities, to ensure good communication and effective cooperation in times of need.
And how do you plan for civil unrest?