Ticha Na Nakorn said on Tuesday she resigned from the National Reform Council (NRC) and the Constitution Drafting Committee because she despaired of convincing a majority of the CDC to agree to a quota of at least one-third of positions in the political arena for women.
She said some CDC members were totally opposed to the proposed ratio.
Ms Ticha's explanation confirmed speculation she resigned from both the NRC and the CDC because of a conflict in the committee over the recognition of gender-disparities in decision-making areas.
The women's rights advocate said it was not easy for women to get decision-making power in the formulation of public policies, mainly because the roads to local and national level politics were designed by men and for men.
It was essential that the constitution drafters explore ways of ensuring a better gender balance.
Ms Ticha said her proposal for a quota of at least one-third caused an uneasy atmosphere in the CDC. The issue had been raised for consideration and left inconclusive on at least three occasions.
A majority of the CDC disagreed with her and insisted in calling a vote to end the debate, she said, resulting in her proposal being finally dropped.
Ms Ticha said she was satisfied with CDC chairman Bowornsak Uwanno's attempt to persuade the two sides to reach a compromise, to no avail.
She decided to resign from both the NRC and CDC because it seemed to her she would not be able to do what she felt should be done to bring about change in society.
She said she had no conflict with anyone. Her resignation was not a show of opposition to the National Council for Peace and Order, but she would definitely not change her mind and resume her seat on either body.
Ms Ticha also expressed concerns over several other issues which remained undecided. They included a proposal that the House or Senate speaker have the power to order the release of MPs or senators who are arrested, and the selection of candidates for seats on the National Human Rights Commission and the Office of the Ombudsman, which she said should require the people's participation.
On a proposal that a non-elected person could be prime minister, she said there should be a clear criterion that would be allowed only in an emergency situation, and must not be used as a special channel for a financial backer of a political party, or anyone holding an extraordinary power, to step in and take the premiership.
On the "ethics assembly" bill passed by the NRC yesterday, Ms Ticha said she was of two minds - it turn out to be either a solution to the country's problems, or a "cemetery" for retired government officials.