Updated

An American woman has accused a Filipino senator of plagiarizing her blog during an acrimonious debate on a contraceptives bill that has divided this predominantly Roman Catholic nation.

Sen. Vicente Sotto III denied using part of Sarah Pope's blog when he argued against the bill to distribute contraceptives in government-run health clinics. But the senator's chief of staff, Hector Villacorta, later acknowledged that they had used her blog without attribution.

Soon after Sotto's speech, Pope, who lives in Florida, started receiving messages from the Philippines about it and soon her blog was swamped with reactions and comments. She made a blog posting Thursday criticizing the senator as "a lying thief."

On Thursday, Sotto told ABS-CBN television that both of them cite the same source, Russian-born Dr. Natasha Campbell-McBride, who claims that contraceptives cause an imbalance between good and bad bacteria in the intestines that breaks down defense against infection.

"Why would I quote from a blogger? She is just a blogger," Sotto said.

Villacorta said he saw nothing wrong with using Pope's blog without attribution because it "is public domain" and "blogs are not covered by copyright."

"It is a new media and there is no jurisprudence yet," he said.

The contraceptives bill is still being debated in the Senate and facing amendments in the House of Representatives. It is unclear when a final version will be put to a vote.

Conservatives and the Catholic Church oppose the bill, saying contraception is the same as abortion, which is illegal in the Philippines.