Tamayo Marukawa, Japan’s new minister for the Tokyo Olympic and Paralympic Games, has come under fire for joining a campaign against a selective dual surname system for married couples.

Gender equality is one of Olympic ideals, and Marukawa concurrently serves as minister for gender quality. A growing number of politicians across party lines are questioning her qualification for the ministerial posting.

Marukawa and conservative lawmakers of the ruling Liberal Democratic Party have asked local assembly members in writing to prevent the adoption of petitions calling for a selective dual surname system. Such a system would lead to the collapse of a social system based on family units, the document said.

The document, dated Jan. 30, was endorsed jointly by 50 lawmakers from both chambers of parliament, including former internal affairs minister Sanae Takaichi and Keiji Furuya, the former chairman of the National Public Safety Commission.

According to sources, the document was sent to about 40 prefectural assembly heads affiliated with the LDP.

The joint request was made before Marukawa, an LDP lawmaker, assumed the post of Olympic and Paralympic minister on Feb. 18. But she told a news conference on Feb. 24 that she had signed the document in line with her personal beliefs.

After an opposition lawmaker urged her to create a system enabling married couples to use different surnames at a House of Representative committee meeting on the same day, Marukawa only said her role is to support an environment that allows people to hold in-depth discussions.