Wilson and Kellig suggested the broken window thesis - the idea that if 'incivilities' are ignored (such as broken windows, petty crime, vandalism), more serious crime will follow. The minor breaches of disorder weaken the bonds in a community - the way to deal with this is for the law enforcers to have a policy of 'zero tolerance' where all crime and misdemeanour, no matter how trivial, is dealt with to prevent an escalation into more serious crime and anti-social behaviour.