Samak's government actively sought to amend the 2007 Constitution, and as a result the PAD regrouped in May 2008 to stage further anti-government demonstrations. The PAD accused the government of trying to grant amnesty to Thaksin, who was facing corruption charges. It also raised issues with the government's support of Cambodia's submission of Preah Vihear Temple for World Heritage Site status. This led to an inflammation of the border dispute with Cambodia, which later resulted in multiple casualties. In August, the PAD escalated its protest and invaded and occupied the Government House, forcing government officials to relocate to temporary offices and returning the country to a state of political crisis. Meanwhile, the Constitutional Court found Samak guilty of conflict of interest due to his working for a cooking TV programme, terminating his premiership in September. Parliament then chose PPP deputy leader Somchai Wongsawat to be the new prime minister. Somchai is a brother-in-law of Thaksin's, and the PAD rejected his selection and continued its protests.^[81]

Living in exile since the coup, Thaksin returned to Thailand only in February 2008 after the PPP had come to power. In August, however, amid the PAD protests and his and his wife's court trials, Thaksin and his wife Potjaman jumped bail and applied for asylum in the United Kingdom, which was denied. He was later found guilty of abuse of power in helping Potjaman buy land on Ratchadaphisek Road, and in October was sentenced in absentia by the Supreme Court to two years in prison.^[82]

The PAD further escalated its protest in November, forcing the closure of both of Bangkok's international airports. Shortly after, on 2 December, the Constitutional Court dissolved the PPP and two other coalition parties for electoral fraud, ending Somchai's premiership.^[83] The opposition Democrat Party then formed a new coalition government, with Abhisit Vejjajiva as prime minister.^[84]