Have legislation doesn't necessarily reduce or eliminate the noise nuisance. Unless the alternative keyholder is a highly trusted near neighbour the alarm will still go off and probably stop sounding by the time that a designated key holder turns up. This is assuming that a home alarm has been designed and set up for a sounding period of no more than
15 minutes. It also assumes that the alternative key holder knows how to operate an alarm that that may not be familiar to them and that they have been given the correct codes to disable the alarm.It is very unlikely that the Police will turn up to a domestic alarm unless it is being monitored by a third party monitoring company.