According to Taiwan media reports, Chen said: "I'm sorry to everybody." He also expressed readiness to make family members and friends face the "sternest investigations" if they are accused of illegal activity.

"I will not shield their faults under any circumstances," he said on the sixth anniversary of coming to office.

For the remaining two years of his final term, he has told family members to stay away from public undertakings and avoid seeking gains.

In one scandal, Chen's son-in-law, Chao Chien-ming, a doctor, was accused of insider trading and was compelled to resign from the Democratic Progressive Party on Thursday.

He apologized but denied any wrongdoing. Chao offered to make a charitable donation from some of profits his mother made from trading shares in real estate developer Taiwan Development Corp.

A telephone poll by the United Daily News on Wednesday showed that just 20 percent of respondents approved Chen's performance - the lowest since he won the 2000 presidential election.

A poll by Shih Hsin University gave Chen an approval rating of 16 percent.

DPP chairman Yu Shyi-kun also bowed and apologized on Saturday after putting on a street cleaner's vest and doing volunteer work. He pledged to improve government performance and eradicate corruption.