Eastern or Checker?

[Didymus20X6]

A friend of mine recently found and safely relocated a garter snake. He posted the following pictures and video for identification. I think it's an Eastern, but another friend, who happens to be a herpetologist from Texas, thinks it's a checker. I've handled lots of Easterns, and am fairly certain that's what it is, but I wanted confirmation before I go telling a professional that he's mistaken. So what do you guys think? Eastern or checker?

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https://www.facebook.com/rick.sawyer.399/videos/4282109678470820/

[indigoman]

Eastern, no question.

[Didymus20X6]

Thanks!

[Eddie]

Eastern for sure. Somewhere in the world there is the worst doctor in the world and someone has an appointment with that person tomorrow