Bangkok - Thailand's state prosecutors announced Thursday that they do not intend to target charges against American scholars arrested for royal defamation, a crime that can be sentenced to up to 15 years in prison.

Paul Chambers, a political science lecturer at Naresuan University in Phitsanulok, Northern Province, was arrested last month, attracting academic attention, especially Asian studies scholars from around the world, as well as the U.S. government

The decision did not prosecute the 58-year-old Oklahoma native and did not immediately clear the allegations of his insulting the monarchy (also known as "Lèse Majesté") or related allegations involving violations of the Computer Crime Act, which covers online activities.

The announcement said that the provincial prosecutors of the province will ask the provincial court to remove the charges and forward the case files and non-procuratorial orders to the commissioners of the provincial police station No. 6, covering Phitsanulok, who may review and challenge the decision.

Chambers, a 58-year-old Oklahoma native, holds a PhD in political science from Northern Illinois University and was arrested in early April for a complaint from the Army's Internal Security Operations Command at the Northern Regional Office.

He studied the power and influence of the Thai military, which plays an important role in politics. It has launched 13 coups since Thailand became a constitutional monarch in 1932, the last 11 years ago.

The Army's Internal Security Operations Command told the parliamentary investigation that it was proposed based on a Facebook post that translates the website of Singapore's Iseas - Yusof Ishak Institute, a think tank in Singapore, which introduced webinars on Thai politics, which included Chambers as participants.

Chambers supporters say the webinar's work was cited as evidence in his charging sheet, which he didn't write.

He was sentenced to two nights in jail in April after reporting himself to Phitsanulok police and was released on bail, with several conditions including wearing an ankle monitor. The court allowed him to remove the equipment Tuesday.

Chambers’ visa revoked at the time of arrest was revoked under immigration laws, prohibiting access to foreigners who are believed to be likely to be in the opposite direction of public order or good morals, prostitution, people’s smuggling and drug trafficking. It is not clear whether the revocation will continue.

"This case intensifies our long-term concern about Thailand's use of Lèse Majesté law," a U.S. State Department statement after the arrest of the U.S. State Department said. "We continue to urge Thai authorities to respect freedom of expression and ensure that the law is not used to stifle the allowed expression."

Thailand's Lèse Majesté law requires any person who slanders, insults or threatens the king, queen, heir or regent for three to 15 years. Critics say it is one of the toughest laws anywhere and is also used to punish critics of the government and the military.

Monarchy has long been regarded as a pillar of Thai society, criticizing it once was a strict taboo. Conservative Thais, especially in the military and courts, still believe this is unreachable.

But over the past decade, especially among young people, public debate on the topic has grown louder, with student-led pro-democracy protests starting in 2020.

This led to violent prosecutions of previously rarely used laws. A legal aid group Thailand human rights lawyer said more than 270 people, many of whom are student activists, have been charged with violating the law since the beginning of 2020.