[grotesqueness]

Yes and the police should inform him of his rights and what he needs to do and address his concerns and queries about the law.....

in singapore 

everyone must show ID to the blues in UNIFORM!
IN UNIFORM!

you can refuse to show ID to those NOT in UNIFORM l
people not in uniform are .....
people on the street 
your employer
and plain cloth CID do not have the right to ask for ID


plain cloth CID need to ask for police in uniform to be presence to ask you for ID 

that is how is works