The government is planning to introduce the right to plea bargain by putting into effect a revised law on criminal proceedings on June 1, government sources said Wednesday.
While the system is expected to help tackle organized crime, lawyers and legal scholars have warned that it could trigger false statements leading to charges being brought against innocent people.
Under plea bargaining, prosecutors may agree not to indict or to seek prosecution for less serious offenses if the suspect or defendant provides evidence and testimony against accomplices in drug, fraud, bribery and other cases.
The crimes of murder and robbery will not be covered under the system.
The law permits plea bargaining only if a suspect or defendant agrees to the conditions set by prosecutors and the defense lawyer's consent is given. If statements are found to be false, those giving them will face up to five years in prison.
After final talks with the ruling Liberal Democratic Party, Prime Minister Shinzo Abe's Cabinet will formally approve the date the legislation enters into force.
The revised law was enacted in May 2016 and is due to take effect within two years of that date.
The legal revision was part of an overhaul in the country's criminal proceedings, which included a stipulation requiring police and prosecutors to record interrogations of suspects in certain serious cases subject to lay judge trials. That revision is supposed to come into effect by June 2019.
The number of cases subject to audiovisual recordings to improve the transparency of investigations is limited to around 3 percent of total offenses. Still, investigators claimed the recordings would make it harder for them to obtain statements from suspects, which prompted them to seek the introduction of plea bargaining as an alternative method to collect evidence.