The New Zealander cited Warburton's conversation with official Steve Walsh during the decisive Six Nations match against England earlier this year - when he was not even Wales captain - as an example of his ability to connect with referees.
He also highlighted the player's good relations with South African official Craig Joubert, who will take charge of the second Lions Test against Australia in Melbourne on June 29.
"There are only two or three players in the world that referees would allow to (talk to them)," Gatland told the Sunday Telegraph.
"It's the ability Sam has to communicate with referees and when I saw that against England. it really stuck in my mind that this guy could do a job for us and potentially have a positive influence on the game with his relationship with referees.
"I think Craig has got a really good relationship with Sam. Having spoken to Craig I know that he regards Sam as one of the best sevens in the world. He regards him on a par with (Richie) McCaw and (David) Pocock in terms of the way he is at the breakdown, his physicality and the way he carries.
"So when a referee makes these comments to you in terms of enjoying his leadership and saying that he's got a good rapport with him, it makes it a kind of easy decision for me to make in terms of appointing him as captain."