ree former and present senior City Hall staff yesterday denied charges brought against them over the extension of the BTS electric train system contract.
They entered their pleas at the Department of Special Investigation (DSI) after acknowledging the charges.
The accused are former city clerk Charoenrat Chutikan, city clerk Ninnat Chalitanont and director of the Bangkok Metropolitan Administration's (BMA) Traffic and Transportation Department, Thana Wichaisarn.
The agency charged them with making an unauthorised contract without seeking the consent of the interior minister.
Pol Lt Col Thawal Mangkhang, a DSI special investigations expert, said the three insisted they acted in accordance with the constitution and applicable laws.
Police quoted Mr Charoenrat as saying he was only completing a bureaucratic process, and was not actually involved in the decision-making, when he signed his name to extend the contract of the Bangkok Mass Transit System Plc (BTSC).
Ms Ninnat said the BMA did not extend a concession to the BTSC.
The concession would still expire as planned, when ownership of the train system would transfer to the BMA. The BTSC would merely operate the system for City Hall under the new contract.
Pol Lt Col Thawal said the DSI has asked for additional evidence from the three within 15 days and will later decide if their cases should go to court.
The DSI is taking legal action against the BMA for extending the BTSC's services on its original and extended routes.
The BMA's contract decision, made last year, raised eyebrows as it took place 17 years before BTSC's 30-year concession expires.
Former Bangkok governor MR Sukhumbhand Paribatra, who is running for re-election on the Democrat Party ticket, is a key target of the probe.
Pol Lt Col Thawal said the DSI also will investigate if the BMA acted improperly in hiring its subsidiary Krungthep Thanakom Co to operate trains on extended routes on the Silom Line for three years and the Sukhumvit Line for one year without consulting the minister.
He said these contracts were signed during the transition of power between former governor Apirak Kosayodhin and his successor MR Sukhumbhand in 2009.