If you say that someone screams blue murder or screams bloody murder, you are emphasizing that they are making a lot of noise or fuss about something that they do not like.
[informal, emphasis]
People are screaming blue murder about the amount of traffic going through theirtown.
See full dictionary entry for murder
blue murder in British English
noun
informal
a great outcry, noise; horrible din (esp in such phrases as cry, howl, scream, etc, blue murder)
Examples of 'blue murder' in a sentence
blue murder
Within seconds all the usual pressure groups were screaming blue murder.
Times, Sunday Times (2012)
They would all be screaming blue murder.
The Sun (2008)
Mum hit the roof and screamed blue murder.
The Sun (2012)
And when trouble occurs we scream blue murder and demand money.
The Sun (2014)
But he admits that just because he is not screaming claret and blue murder at his blundering players does not mean he is not furious inside.
The Sun (2015)
If the police don't get a result at the end of all this, people will be screaming blue murder.
The Sun (2006)
You all scream blue murder when WHSmith pockets 20 per cent of your airport spend to boost its bottom line when you hand over your boarding card.
The Sun (2015)
Definition of 'blue murder scream blue/bloody murder'