The crowds present in Washington DC for the Presidential Inauguration and the Women's March have made international headlines. One important perspective on the numbers has come from Institute Fellow Professor Keith Still and his colleague Marcel Altenburg at Manchester Metropolitan University. They are crowd scientists who work extensively on crowd safety and risk analysis but who have developed methodologies to assess crowd numbers.

The New York Times carried a detailed article on 22nd January based on the analysis they had undertaken which suggested that whilst around 160,000 were in the National Mall and vicinity in the hour prior to the Inaugural Address, crowds of 470,000 were present during the Women's March.

In the New York Times article, Marcel Altenburg explains why it may have appeared differently to those on the podium (President Trump stated that there were somewhere between one million and one and half million people on the National Mall). The crowd would have appeared very thick at the front nearest the podium but the analysis undertaken by the crowd scientists included data from seven live feeds covering much further back along the Mall where crowds were far more sparse.

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