Between 1990 and 2005, there was an average of five new lèse-majesté cases per year. Since then, however, there have been at least 400 cases—an estimated 1,500 percent increase. Prior to the 2006 coup, targets of lèse-majesté were mostly politicians, high-ranking bureaucrats and extra-constitutional figures, but after 2007, common people were charged.  The law had been interpreted to cover past monarchs and symbols associated with the monarch. No one had been sentenced to more than ten years in jail before 2007. Observers attributed the increasing number of lèse-majesté cases to King Bhumibol's public invitation of criticism in 2005, increased polarisation following the 2006 military coup, and to speculation over his declining health in the period before his death in 2016.

In 2005, cases registered in the Attorney General's office rose sharply from 12 new cases in 2000–2004 to 17.  Thai Rak Thai and Democrat Party as well as opposition movement People's Alliance for Democracy traded lèse-majesté accusations.  Former Prime Minister Thaksin Shinawatra's alleged lèse-majesté was one of the stated reasons for the Thai military's 2006 coup. After the coup, dozens of radio stations were shut down because of alleged lèse-majesté.

Academics have been investigated, imprisoned, and forced into exile over accusations of lèse-majesté. Prominent historian Somsak Jeamteerasakul was arrested for proposing an eight-point plan to reform of the monarchy. Professor Giles Ji Ungpakorn went into exile in 2007 after his book, A Coup for the Rich, questioned Bhumibol's role in the 2006 coup. In March 2011, Worachet Pakeerat, a law lecturer, banded together with same-minded lecturers and formed the Nitirat Group, aiming to amend the lèse-majesté law. He proposed reducing the maximum jail term to three years, a circumstance for pardoning, and that only the Office of His Majesty's Principal Private Secretary could file a complaint. His actions angered many people. In February 2012, he was assaulted in broad daylight in Bangkok.

During the government of Yingluck Shinawatra, the number of arrests and convictions for lèse-majesté offences declined significantly. However, she said she would not seek to reform the law. There were 478 cases in 2010. In May 2014, the National Council for Peace and Order (NCPO), the military junta, granted authority to a military tribunal to prosecute lèse-majesté in Thailand. Military courts routinely imposed harsher sentences than civilian courts would.

In August 2015, the Bangkok Military Court sentenced Pongsak Sriboonpeng to 60 years in prison for his six Facebook postings (later reduced to 30 years, when he pleaded guilty). This was Thailand's longest recorded sentence for lèse-majesté. The courts were dubbed "kangaroo courts." The military government has never successfully extradited someone living abroad.

iLaw, a Thai non-profit organisation, reported that the junta hold persons in custody for seven days without charges. Secret trials were held. Officials seized personal communication devices to search for incriminating evidence.

In December 2014, the parents of Srirasmi Suwadee, formerly a Thai princess, were sentenced for "insulting the royal family and lodging a malicious claim".

In 2015, Prachatai published an infographic showing that bathroom graffiti, a hand gesture, a hearsay report of a taxi conversation, and reports of not standing during the playing of the royal anthem, among other things, could be punished as acts of lèse-majesté. A nurse wearing black on Bhumibol Adulyadej's birthday was charged with lèse-majesté.

The last formal attempt to amend the law occurred in May 2012 when more than 10,000 people signed a petition to parliament, but Speaker of the House of Representatives, Somsak Kiatsuranont, dismissed it citing that amendment of the law concerning the monarchy was not a constitutional right.