In recent years it has become apparent that violent groups of people are covering their faces at public events in order to remain anonymous. This increases the possibility of violence ensuing due to the belief that they will not be held accountable as they cannot be identified.
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There are more political activist groups now more than ever before possibly due to current political climate along with the power of social media (YouTube, FaceBook, etc). Left-wing groups such as ANTIFA and right-wing groups such as the EDL are able to muster large numbers of activists on the streets committing violent acts with complete anonymity. In order to help contain these groups and prevent and/or reduce the amount and levels of violence, wearing of a face mask in public must be banned.