James 2:9

9 But if you show favoritism, you sin and are convicted by the law as lawbreakers.

Read James 2:9 Using Other Translations

But if ye have respect to persons, ye commit sin, and are convinced of the law as transgressors.
But if you show partiality, you are committing sin and are convicted by the law as transgressors.
But if you favor some people over others, you are committing a sin. You are guilty of breaking the law.