Killing of PC Doyle is a 'Christmas tragedy'

Peter Singleton, chair of the Merseyside police federation spoke to Today's Justin Webb about the "devastating news" of the death of PC Doyle.

"It is a worrying incident for police officers."

Speaking about off duty police officers, Singleton said that they "may not have the freedom of choice as other members of the public."

First broadcast Today programme 20 December 2014.