It is reported that in the 1870s, 20,000 criminals were living in London. Crime had become a matter of great concern to the police and the philanthropists. Police was worried about the law and order and the philanthropists were anxious about public morality. The industrialists wanted a hard-working and orderly labour force. According to Henry Mayhew, who wrote several books on London labour, the ‘criminals’ were in fact poor people who lived by stealing lead from roofs, food from shops, lumps of coal,clothes drying on hedges. Others were more skilled in their trade, experts in their jobs. There were cheats and tricksters, pickpockets and petty thieves crowding London streets. The main reason was the huge population of London, less number of jobs and the poverty of the majority which made it a city of crime.