The Government should make it illegal for any type of spikes or sharp edges on top of fences in residential areas, as these can harm animals and humans.
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My cat was injured on a neighbour's fence, they had used chicken wire and left all the sharp edges, which created a hazard. In addition, if a neighbour has installed sharp objects on a fence adjoining my property, and someone in my property injures themselves on this, I could be legally liable.