unpartizan
/ˌʌnˈpɑːrtɪzən/Definitions
1. adjective
not biased towards or favoring one particular faction or party, especially in politics or sports.
“The referee tried to remain unpartizan throughout the game.”
2. noun
a person who is not biased towards or favoring one particular faction or party, especially in politics or sports.
“The unpartizan observer reported on the election results without any bias.”