Definify.com

Webster 1913 Edition

Adj.

Furnishing evidence; asserting; proving; evidential.

When a fact is supposed, although incorrectly, to be

evidentiary

of, or a mark of, some other fact.

J. S. Mill.

evidentiary ‎(comparative more evidentiary, superlative most evidentiary)

(law) Of or pertaining to evidence.
Evidentiary investigations are common in legal proceedings