A bill that’s currently making its way through the New York state assembly would require smartphone manufacturers to build in the ability for law enforcement to decrypt or unlock phones on demand.
- New York bill would give law enforcement a backdoor into your smartphone” TheNextWeb.com

This is no different that asking building doors (Commercial, Home, or otherwise), safes, file cabinets, vehicles, pad locks  and bike locks to be unlock-able with one master key. 

What could possibly go wrong?