The Yala Provincial Court on Thursday jailed a blind woman for 18 months for lese majeste, her lawyer and a court official said.
Nurhayati Masoh, 23, was found guilty after she posted on her Facebook account an article by Giles Ungpakorn, a Thai-British academic and vocal opponent of the monarchy who fled Thailand after he was charged with lese majeste in 2009.
"She confessed that she posted it," Kaosar Aleemama, a lawyer for Nurhayati, told Reuters. "But she did not realise it would lead to such a harsh punishment."
Ms Nurhayati, who uses a computer application that helps the visually impaired to post on social media, was arrested in November and sentenced to three years in jail by the court.
"The case against her was filed on Nov 28, 2017 and she has been detained since," an official at the Yala Provincial Court, who declined to be named, told Reuters.
Ms Nurhayati's confession led to her sentence being halved, he added.
Since the 2014 coup, at least 94 people have been prosecuted for lese majeste. As many as 43 people have been sentenced, accoording to the iLaw group that monitors royal insult cases, with 92% of them pleading guilty in hopes of receiving a shorter jail term.
"There may be more cases that we do not know about," Yingcheep Atchanont, iLaw's project manager, told Reuters.
The United Nations has expressed concern over what it calls a deteriorating rights situation in Thailand, including harsh sentences for those convicted of violating the lese-majeste law, or Section 112.
The ruling generals have said they need to crack down on critics of the monarchy for the sake of national security.