OXFORD
fair to somebody (to do something) Was it really fair to him
to ask him to do all the work?
fair on somebody (to do something) It's not fair on the
students to keep changing the timetable.
fair to do something It's only fair to add that they were
not told about the problem until the last minute.
CAMBRIDGE
It's not fair on Joe (= it is not right) to make him do all the work!I
t's not fair that she's allowed to go and I'm not!I
t's not fair to blame me for everything!
She's scrupulously fair with all her employees (= she treats them all
equally).
MACMILLAN uvádí i spojení “fair in”
Teachers have to be scrupulously fair in marking examination papers.
MERRIAN – WEBSTER uvádí obě možnosti – jak “fair to”, tak
“fair with”
I try to be fair to/with my children.