The first thing we should do is look for which police line seems the weakest and with the best chance of escape should we break the line. This may be a line of normal cops without riot gear and usually only one officer deep. Here how the work might proceed.
In Fig 1 we see the crowd attempt to break the police line by using opposing force. This can sometimes work but usually the police can brace themselves and hold each other and thus hold the line. In this way, the strength of the crowds' force is lessened and absorbed by the police line.
In Fig 2 we the crowd attempt to get technical and use a banner or metal barrier to push the police. The same dynamic occurs again and the crowds' force is lessened and absorbed by the police line.
In Fig 3, the crowd has decided to form a wedge shape to drive a gap in the police line and follow though, the thickness of the crowd opening more and more of the police line up.
In Fig 4, the crowd knows that the police line weak points are at the extreme ends of the line as the final policeperson has no brace or support. The crowd attempts two pushes on the line at the weak points.
Mrs Nov 30th