Why did Jon Snow kill the Night's Watch guy?

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Tags

1. #engages
2. #halfhand
3. #never
4. #authority
5. #wanted
6. #fight
7. #happen
8. #really
9. #ranger
10. #watch
11. #claiming
12. #leads
13. #wildlings
14. #night
15. #which
16. #convince
17. #despised
18. #qhorin
19. #their
20. #intended