Thai people are increasingly fretting over corruption as the government revs up big-ticket infrastructure investment, a poll by the University of the Thai Chamber of Commerce (UTCC) reveals.
According to the latest survey of 2,400 respondents in the private and public sectors, the corruption situation index (CSI) dropped to 53 points in June from 55 points in December.
A lower CSI score indicates higher levels of corruption, while a score of 100 shows high transparency and a lack of graft.
Sauwanee Thairungroj, president of the UTCC, said people were concerned about greater room for corruption as procurement for state projects gets under way.
The government aims to start construction of 20 megaprojects valued at 1.6 trillion baht this year as part of a plan to stimulate the economy.
The cabinet has already approved 11 projects worth 460 billion baht that are due for completion by 2022. Private investment accounts for 25% of total investment.
The government is also opening bids for three mass-transit routes in Bangkok, the Pink Line from Khae Rai to Min Buri, the Yellow Line from Lat Phrao to Samrong and the Orange Line connecting Thailand Cultural Centre with Min Buri.
It is also committed to increasing investment in two high-speed rail projects, the 194-kilometre Bangkok-Rayong route, worth 153 billion baht, and the 211km Bangkok-Hua Hin route, worth 94.7 billion baht.
The two high-speed rail projects will promote connectivity between Thailand and neighbouring Cambodia, Laos, Myanmar and Vietnam.
"People see that weak law enforcement and a lack of transparency in the political process are some of the root causes of widespread corruption in Thailand," said Ms Sauwanee.
She added that common acts of graft include giving bribes, presents, and various forms of rewards and awards.
The UTCC's latest survey published earlier this year found that bribes paid by businesses to state officials and politicians was 1-15% of the procurement budget and biddings for state enterprises in 2015 -- unchanged when compared with the previous survey conducted in December last year.
This is equivalent to 10-178 billion baht, accounting for 0.42-1.27% of GDP.
Ms Sauwanee said the situation has improved since 2010-13, when corruption occurred at a rate equivalent to 25-35% of the procurement budget and biddings, costing Thailand 323-330 billion baht a year.