The Pollution Control Department welcomes corruption investigations but says a survey ranking it highest for bribe offers reflects only private sector perceptions, not proven facts, and questions the study's methodology and small sample siz
The Pollution Control Department (PCD) affirms its readiness to open itself fully to corruption investigations, stating that the survey results from the Private Sector Joint Committee (PSJC) represent perception-based information and should not be used to rank government agencies or reflect the country's overall corruption picture.
On May 25, 2025, at the Pollution Control Department, Surin Vorakitdhammrong, Director-General of the PCD, announced the department's assessment of research documents from the PSJC's survey of opinions claiming the PCD received the highest average bribe offers at 102,160 baht per instance. Upon learning of the survey results, the PCD immediately convened nationwide administrator meetings and sent an open letter to the PSJC on May 15, 2025, requesting clarification of data sources, verification methods, and submission of relevant evidence within 7 days. This would allow the PCD to verify whether officials were actually involved in corruption.
The PSJC submitted an explanatory letter outlining survey principles and methodology to the PCD on May 22, along with supporting documents including a survey procedure summary, sample questionnaires, and materials accompanying the public announcement.
Director-General Surin stated that the PCD does not reject corruption investigations; rather, it welcomes thorough examination. Corruption undermines the economy, investment, and public confidence. If officials are found to have violated regulations, the PCD will take decisive disciplinary action without exception. The department has established a working group to review measures and administrative practices at every stage to prevent corruption, particularly in law enforcement and inspection procedures dealing with pollution sources—areas where there is risk of abuse of authority and position.
The PCD Director-General emphasized a key point: the survey results constitute "perception-based data," meaning information reflecting the feelings, beliefs, or experiences of survey respondents during a specific period—not facts verified through formal legal proceedings. Such data should be used to reflect private sector perspectives or confidence trends rather than to conclude that corruption actually occurred at the institutional level.
Reviewing the PSJC's documents, Director-General Surin identified several methodological concerns. The survey classified government agencies into 5 groups and sampled only 26 agencies out of 162 ministry-level agencies nationwide, which the PCD views as insufficiently representative of Thailand's overall civil service system and inadequate for establishing national-level policies on academic grounds.
Additionally, the questionnaire design referenced World Bank guidelines from 1999, which may not align with current roles and missions of many agencies. The sample size comprised only 401 respondents nationwide, surveyed over 16 days by individuals with direct experience—approximately 45 percent, averaging roughly 7 people per agency. Some survey questions appeared leading, such as using phrases like "it is commonly known" or posing negative hypotheticals: if additional payments are not made, processes may be delayed. Furthermore, both online and face-to-face questionnaires were used with different question structures.
According to the PSJC's own explanatory letter, confidence levels and sample error margins reference the overall survey and should not be interpreted as guaranteeing accuracy at the individual agency or sub-issue level. Therefore, the conclusion that the PCD received the highest bribe offers may not accord with research standards and ethics. Director-General Surin noted the PCD's previous cooperative efforts.