Physically disabled people who cannot write by themselves will be allowed to let a proxy fill in their mail-in ballots under a law passed Friday by the Diet.
The law will allow some 130,000 disabled voters nationwide to cast their ballots in the House of Councilors election next summer.
It allows proxies to fill in mail-in ballots for people who cannot write by themselves and who hold official booklets certifying they are physically impaired or have been wounded in war.
Proxies must be registered in advance at local election boards and will face a punishment of up to two years in prison or 300,000 yen in fines if illegal practices are found.
The law also allows mail-in ballots by those who receive home-care services under the highest grade of the public insurance scheme. Such people, now totaling about 120,000 nationwide, are required to fill in the ballots themselves.
The revision came after the Tokyo District Court ruled in a lawsuit last November that the government's refusal to accept mail-in votes written on behalf of physically disabled people who cannot write by themselves violates their voting rights and is unconstitutional.
The court urged lawmakers to revise the election law, although it rejected the damages suit, which had been filed by three plaintiffs seeking a combined 2.7 million yen in compensation from the government.
The plaintiffs included people with Lou Gehrig's disease, which causes sufferers to eventually lose motor control and become paralyzed.