Japan is set to open an execution chamber to the media for the first time, after the justice minister attended the hangings of two inmates in July and called for more debate on capital punishment.
Japan and the United States are the only countries in the Group of Eight rich nations that conduct executions.
Following are key facts on the death penalty in Japan and around the world.
* Japan executed 7 people in 2009. Since 2007, the justice ministry has released information on those who have been hanged after the execution, such as their names and the crimes they committed.
* Death row inmates are kept in solitary confinement in 7 detention centres throughout the country. Currently, there are 107 of them.
* The death row inmates are notified on the morning of the execution day that they will be executed, usually about an hour before the execution. The UN committee against Torture has criticised Japan for "the psychological strain" on inmates and their families over the uncertainty of the execution timing.
* Execution is by hanging. Medical experts have said that a person who is hanged immediately loses consciousness and their heart stops in about 15 minutes.
* While the law says an execution must take place within six months after the sentence is finalised by the court system, in practice it usually takes several years. Among 30 executions that took place in the 10 years from 1997, the average period was 7 years and 11 months. Some inmates have been in solitary confinement for over 20 years.
Around the world
* There are 58 countries that still retain capital punishment, while 104 countries have abolished it and 35 have stopped executions in practice.
* At least 714 people were executed in 2009, though the total does not include China, which did not provide a figure.
* The 18 countries known to have conducted executions in 2009 were: Bangladesh, Botswana, China, Egypt, Iran, Iraq, Japan, Libya, Malaysia, North Korea, Saudi Arabia, Singapore, Sudan, Syria, Thailand, the United States, Vietnam and Yemen.
* Hanging, shooting, beheading, stoning, electrocution and lethal injection are common methods of executing people.
* The countries that executed the most people include Iran with at least 388, Iraq at least 120, Saudi Arabia at least 69, and the United States with 52. But China has likely conducted more executions than the rest of the world combined.
* There are 35 countries that in practice have a moratorium on executions. These are Algeria, Benin, Brunei, Burkina Faso, Cameroon, Central African Republic, Eritrea, Gabon, Gambia, Ghana, Grenada, Kenya, Laos, Liberia, Madagascar, Malawi, Maldives, Mali, Mauritania, Morocco, Myanmar, Nauru, Niger, Papua New Guinea, Republic of Congo, Russia, South Korea, Sri Lanka, Suriname, Swaziland, Tajikistan, Tanzania, Tonga, Tunisia and Zambia.
* In the United States, death sentences and executions have been falling due to heated debate about innocent people being put to death, as well as the high costs of the process, including facilities and trial costs. There was a de-facto moratorium on executions from late 2007 to early 2008 as the Supreme Court heard a challenge to the lethal injection method, which it rejected in April 2008.