conscionably
/ˈkɒnʃ(ə)nəbli/ /ˈkɒnʃ(ə)nəbli/adverb
1According to conscience, with a good conscience; conscientiously, scrupulously.
2Equitably, reasonably, fairly.
Origin
Mid 16th century; earliest use found in Richard Huloet (fl. 1552), lexicographer. From conscionable + -ly.