The Democrat Party, which celebrated its 68th anniversary yesterday, boycotted the Feb 2 election, called after caretaker Prime Minister Yingluck Shinawatra dissolved the Lower House last December.
Democrat secretary-general Juti Krairiksh said the party had refused to join the election because it was unfair.
He said the Election Commission had repeatedly stated it could not guarantee a fair election, but the caretaker government insisted on going ahead with it in a bid to whitewash its wrongdoings.
He said the Democrat Party placed importance on election atmosphere.
The present situation was not conducive to an election because government supporters continued to threaten independent organisations, the people and political parties which opposed it. The police had also failed to perform their duties impartially, Mr Juti said.
He pointed out that unless an election was fair, it would not be democratic.
He called on Ms Yingluck to ensure a fair election.
Mr Juti claimed Ms Yingluck had never asked pro-government and red-shirt demonstrators to behave, and this had suggested that she supported the actions of red-shirt demonstrators.
Mr Juti said society had already witnessed red-shirt demonstrators threaten other party members without facing arrest.
The Democrat Party has also been threatened, he said.
Mr Juti said during the 2005 general election, a political canvasser belonging to his party in Phichit province had been told to stop his campaigning.
When the threat was ignored, the canvasser was shot dead in front of his house three days before the election. Police have still not arrested any suspects, Mr Juti said.
He said the present situation was worse. Anti-government demonstrators were being ambushed and no suspects had been arrested.
Under such circumstances, Democrat Party members wondered if it was safe for them to go campaign for votes.
“The [Democrat] party conducted a survey of potential candidates nationwide and found that 80% had no safe place to campaign for votes, except those in the South, Bangkok and parts of the Central Plains.
“So, we wonder if a free and fair election can happen if one political party can campaign for votes but another cannot,” the Democrat secretary-general said.
He intended to inform the Election Commission about the situation at a meeting with political parties on April 22. The Democrats would also ask the EC if it could protect retired government officials who were provincial election authorities from such illegal influences.
Mr Juti said the present situation in Thailand reminded him of the era of former Filipino president Ferdinand Marcos, when plainclothes police had been used to murder his opponents, and only one family and its associates cashed in and enjoyed power over the country.
The Democrat secretary-general said he believed that, if an election was fair, his party would have a chance of winning.
He said the general public was aware of past corruption and abuse of authority by the current government and the negative impacts on the country associated with the influence of former prime minister Thakin Shinawatra.
Mr Juti claimed that the Democrat Party, meanwhile, has developed a better reputation for proposing national reform and solutions to corruption and inequality.
Although the Democrat Party was unable to predict when the next general election would happen, Mr Juti said that it had planned possible stances for different scenarios, depending on the timing of the fresh poll.
Meanwhile, Democrat leader Abhisit Vejjajiva said he was concerned that people were being misled that when independent organisations and courts issue undesirable rulings, they were trying to overthrow the government and democratic rule.
He said the nation can progress only with a political system that upholds democracy.