Situated, protecting one with one-sided views (6)
I believe the answer is:
biased
'with one-sided views' is the definition.
(having a bias for one side)
'situated protecting one' is the wordplay.
'situated' becomes 'based' (I've seen this in another clue).
'protecting' means one lot of letters goes inside another (inserted letters are held or protected).
'one' becomes 'i' (Roman numeral).
'based' going around 'i' is 'BIASED'.
(Other definitions for biased that I've seen before include "Influenced unfairly" , "Favouring one person or side over another" , "Having favourite" , "Prejudiced or partisan" , "not fair" .)