Thailand has hit a new low in the latest global corruption index, with Mana Nimitmongkol, secretary-general of the Anti-Corruption Organisation of Thailand, urging reform of the civil service and legal system to help combat the problem.
Thailand has fallen another three places in the annual Corruption Perceptions Index (CPI) published this week by Transparency International.
The country ranked 104th among 180 countries surveyed, down from 101st a year earlier, with an overall score of 36 out of 100. Since 2012 when it was ranked 103rd, the country's score has changed very little.
In Southeast Asia, Vietnam shares the same 104th place with Thailand, two spots behind Indonesia. Malaysia ranked 57th with a score of 51 points. Farther down the list were the Philippines (115), Laos (134), Myanmar (137) and Cambodia (160).
The top two countries in the index, Denmark and New Zealand, had a score of 88. They were followed by Finland and Singapore at 85.
The Corruption Perceptions Index, compiled annually since 1995, ranks countries and territories based on perceived levels of public sector corruption, according to surveys of experts and businesspeople.
Mr Mana said that foreign businessmen and investors were concerned that corruption was still a major problem in Thailand, which would have an impact on their confidence in investment in the country.
He said studies also showed that Thai laws governing investment between state agencies and the private sector lacked clarity compared to other countries.
Mr Mana pointed to private investment in the government's flagship Eastern Economic Corridor (EEC), saying privileges given to private investors in the EEC scheme have been criticised for benefiting vested interests.
Thailand has a Board of Investment which offers incentives and privileges to investors, but the government still focused on the public-private partnership (PPP) model for investment in the EEC.
"The laws and policies are already in place. But in practice, there is a lack of clarity in implementing them," Mr Mana said.
"Another key factor is civil servants who have refused to change the way they work. We have been trying to reform the civil service, the legal system, and police force to improve anti-corruption efforts, but no progress has been made."
Juree Vichit-Vadakan, former secretary-general of Transparency Thailand, said the CPI mirrored the general feeling of the nation. She said that tackling graft requires both short-term and long-term measures. Initially, strict law enforcement is needed to punish those involved while the further down the line increased public awareness can help eradicate the core of the problem.
However, she said the CPI's study is based on perception and suggested the more academic Global Corruption Barometer must also be considered.