BANGKOK — The resort hotel in Thailand got its public apology. The unhappy American guest who spent two nights in jail for criticizing the hotel online got his criminal charges dropped. But it was Tripadvisor, the giant online travel review platform, that got the last word.

Wesley Barnes, the American traveler who was arrested after being charged with criminal defamation for posting critical reviews of the Sea View resort on the island of Koh Chang, quietly left Thailand this week.

With Barnes safely out of the country, Tripadvisor took punitive action Wednesday against the resort, posting a one-of-a-kind notice on the Sea View’s page warning travelers that the hotel was behind the jailing of a guest for his harsh reviews.

“Thailand’s use of criminal defamation is really off the charts,” said Phil Robertson, the deputy Asia director for Human Rights Watch. “It seems like the Asian notion of ‘saving face’ has really been taken to heart by Thais who don’t hesitate to head to court over the smallest perceived slight or insult. If Thailand would simply decriminalize defamation, making it a purely civil law matter, this would create a major change in Thai society overnight.”.....