The most common and most likely answer to this crossword clue is the 5 letter word SIOUX
S
I
O
U
X
More clues leading to the result SIOUX
- Half of Iroquois backed by a related group
- Anxious about unarticled Native Americans
- Reportedly charge native Americans
- Some Indians take legal action in hearing
- Boundary enclosing, essentially, four American people
- In hearing, bring a case against native American
- Bring action against vocal group including Crazy Horse
- Crossword Pun:
Buddy explains!

The straight part
We know that "native American" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case native american = sioux.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.