THE Government denied yesterday that it had bowed to pressure in not appointing Tony Samson to head the Buildings Department. A Government spokesman said yesterday that normal procedures and criteria had been followed in naming Helen Yu Lai Ching-ping to the post. Structural engineers in the department had accused Mr Samson, the original front-runner for the post, of mismanagement and said the job must go to a local. ''It is very clear that so-called political factors such as pressure from staff associations cannot be taken into account,'' the spokesman said. ''Furthermore the Public Service Commission is established as an independent watchdog to prevent that sort of thing happening.'' The spokesman said the suggestion that the Government had bowed to political pressure in doing so was untrue. ''In this particular case, it was decided after careful deliberation, in accordance with the promotion criteria that there was no one fully suitable at this stage to be appointed substantively as director,'' he said ''Therefore, following precedents in previous cases we decided to post in administrative officer to lead the department for the time being. ''Seen in this context, Mrs Yu's appointment is in the best interest of this department as a whole,'' he added. Mr Samson is the Principal Government Building Surveyor. The job went to Mrs Yu last week after it had been left vacant for five months. Mr Samson has publicly attacked the Government over the controversy, accusing it of manipulation. He launched a formal appeal to Governor Chris Patten last week and said he might sue the Government on the grounds of unfair discrimination if no detailed explanation was offered. Six senior officials from the department, including Mr Samson, failed in the promotion exercise. The Director of Buildings, a D5 post with a monthly salary of $111,200 was created on August 1 when the Buildings and Lands Department was split into the Buildings Department and the Lands Department.