A professor whose book about Japan’s World War II-era military brothels angered Korean women who once worked there was acquitted on Wednesday of defaming the women.

The professor of Japanese literature at Sejong University in Seoul, Park Yu-ha, published “Comfort Women of the Empire” in 2013. She has since faced civil and criminal complaints from nine South Korean women who said they were forced to work at the brothels during the war.

A year ago, Ms. Park lost a civil lawsuit when a court said she had defamed the women with “false” and “distorted” content in her book and ordered her to pay each of the nine 10 million won, or about $8,500.