Is it socially acceptable to go trick or treating in black face?

No. Racism is never acceptable.

Who is Black face?

If they are a bat or black cat or even batman then yes it is fine.

A bit soon to be thinking of Hallowe'en, isn't it?

How about black, red and purple face?

They claim blackface costumes, especially at Halloween, are just innocent fun. What could be the ... they wear them as tribute. Racist humour pushes the limits of acceptable racial discourse. ... Click here to visit our frequently asked questions about HTML5 video