The red shirts who incited the torching of city halls in 2010 have not faced justice, bolstering suspicions of double standards.
The tough sentences handed down to protesters found guilty of setting fire to city halls during the political unrest in May 2010 have drawn a clear line between legitimate protest and serious crime. Demonstrators will now think twice when their leaders try to incite them to cross that line.
The Supreme Court on Tuesday handed lengthy prison terms to many of the 13 red-shirt protesters found guilty of involvement in an arson attack on Ubon Ratchathani's city hall during the 2010 upheaval.
Six of them were each sentenced to 33 years and four months in jail, while the putative ringleader, Pichet Thabuddha, received life imprisonment after initially being sentenced to death. A core member of the local chapter of the United Front for Democracy against Dictatorship, Pichet was found guilty of inciting the others to light the fires.
The verdicts are the latest fallout from the burning spree that took place in the Northeast during the 2010 rallies.
Last month a lower court in Khon Kaen sentenced red-shirt protesters to between three and 13 years in jail for setting fire to the northeastern province's city hall, while in September three convicted arsonists were each handed 15-year sentences in Mukdahan.
There is little doubt that the arsons were inspired, or even explicitly encouraged, by leaders of the 2010 protest - some of whom are influential politicians or activists.
As tensions between the government and the protesters reached a crescendo that May, red-shirt leaders directed ordinary activists to gather at city halls and "take whatever action was suitable" if the main protest site in Bangkok was dispersed by force. The leaders had repeatedly threatened a "sea of fire" and "a blaze that would consume every corner of Thailand" should the rally in the capital be broken up.
The rhetoric of incitement was directed from above towards ordinary protesters, many of whom responded eagerly in the belief that their leaders would protect them from legal consequences.
Yet, with dismal inevitability, those red-shirt chiefs and politicians were nowhere to be seen when their foot soldiers landed in court. Some of the accused complained of receiving no attention or assistance whatsoever from the protest leadership.
Protesters routinely violate traffic laws, emergency decrees and internal security measures. But those offences cause little or no damage to life or property and are often considered legitimate means of expressing opposition to authority. The committing of severe crimes in the name of political protest - whether or not at the incitement of leaders - cannot be tolerated in a like manner.
Hopefully the string of court rulings against arsonist protesters will discourage similar attacks in the future. Repairing and rebuilding the targeted city halls is costing taxpayers hundreds of millions of baht. Some of the older buildings were considered cultural heritage and are irreplaceable.
Meanwhile cases against the protest leaders - some of them well-known and influential politicians - have progressed slowly. Although several have fled the country, others managed to evade legal fallout for their roles in the violence. To dispel suspicion of double standards, the authorities must do all they can to speed up legal action against those who incited the 2010 melee.
Critics, including several Western diplomats eagerly interested in Thailand's internal affairs, have voiced accusations of double standards and unfair treatment. They might now turn their attention to this issue, and that bodes poorly for the country's reputation.