Former prime minister Abhisit Vejjajiva will also be asked to testify about the abandoned contracts for police buildings approved during his government's tenure, Department of Special Investigation (DSI) chief Tarit Pengdith said on Wednesday.
Mr Abhisit's former deputy prime minister, Suthep Thaugsuban, is already in the DSI spotlight over the failure of the single contractor to complete the construction of 396 police station buildings worth 5.84 billion baht and 163 police flats worth 3.7 billion baht.
Speaking in the DSI's weekly press conference, Mr Tarit said his office had found evidence that eight construction firms had sent a letter to Mr Abhisit and Mr Suthep opposing the decision by the Royal Thai Police Office (RTPO) to give a single company the contract to carry out both projects nationwide.
Originally, the RTPO planned to allow the Region 1-9 Provincial Police Bureaus to individually contract the work in their own areas of jurisdiction. It later switched to preferring giving the contract to one company. The company which won the bidding was PCC Development and Construction (PCC).
Despite the opposition from the private sector, both Mr Abhisit and Mr Suthep still approved change, he said.
Abhisit Vejjajiva, left, and Tarit Pengdith (Photo by Thiti Wannamontha)
"Since the new evidence also implicates Mr Abhisit, DSI investigators handling the case agreed to also invite him in for questioning, in addition to Mr Suthep, in order to be fair to all," Mr Tarit said.
According to Mr Tarit, the eight construction firms strongly asked the two not to approve the change, arguing that doing so would be unfair to prospective regional and local contractors.
They said if they approved the change, only one firm would benefit from the projects - to build 396 police stations and 163 apartments nationwide.
The firms also cited the RTPO's past failure in contracting the National Housing Authority (NHA) to carry out a police housing project because the agency could not complete it by the deadline.
Granting the contract to only one firm was tantamount to allowing bidding price collusion, they said, according to Mr Tarit.
Mr Tarit said it was interesting that the first of the eight construction firms that sent a letter was PCC itself, which later won the two contracts as the sole builder of the two projects.
He said the DSI lately received a complaint from five companies sub-contracted by PCC, saying that they had been cheated even though PCC had been paid more than 1.5 billion baht by the RTPO.
The DSI on Wednesday sent a letter to national police chief Pol Gen Adul Saengsingkaew advising him to file a complaint against PCC for business fraud, Mr Tarit said.
Thanin Prempree, director of the DSI's corruption prevention and suppression centre, said the DSI had asked the RTPO to quickly terminate the contract with PCC without waiting until it expires on March 14.
He said the DSI feared that PCC might opt to be fined in order to get another extension of the contract and buy more time.
The RTPO should terminate the contract so it could call fresh bids for the two projects, he said.
Mr Thanin said PCC, in sub-contracting some of the work out to other firms, might have violated Item 8 of the contract.
Asked whether PCC was linked to a construction contractor in Chiang Mai who is the father-in-law of a well-known politician, he said this was being investigated.
The DSI has also invited three former national police chiefs in for questioning over possible irregularities in the projects. They are Pol Gen Patcharawat Wongsowon, Pol Gen Preteep Tanprasert and Pol Gen Wichean Potephosree.