An arrest in Japan is based on an arrest warrant issued by a judge. The judge acts after the investigating agency has presented evidence demonstrating probable cause to believe that the suspect committed a crime, and that there is a risk of concealing or destroying evidence of the crime. When, as in the case of Ghosn, the prosecutor arrests the suspect and believes that further detention is necessary, the prosecutor will request the judge to detain the suspect within 48 hours. The judge will listen to the suspect's statement regarding the charge and decide if a detention is necessary. The detention period is 10 days; however, the judge may extend it for 10 more days if there are compelling reasons. Requirements for detention of the accused after prosecution are the same as those for detention of a suspect, but the detention period is two months from the date on which the prosecution's case was filed. The court may renew the detention period monthly, upon providing specific reasons. An accused who is released on bail is required to comply with conditions set by the court.
A police officer in France has the power to hold a suspect in custody when the officer concludes there are reasonable grounds to believe that the suspect has committed a crime and that detention is necessary to prevent destruction of evidence. This is called "garde à vue." This restraint period is 24 hours. An additional 24 hours may be allowed with permission from the prosecutor. At the investigation stage, conducted by the investigating judge (juge d'instruction) or at the trial stage, a judge can set compliance rules (contrôle judiciaire). The accused is obliged to observe those rules for the purpose of securing appearance or preventing reoffending. The residence of the accused may be fixed, and s/he may be required to wear a GPS device. Nevertheless, the accused can be detained (détention provisoire) when a judge finds that such measures are not sufficient to alleviate the risks. The detention period depends on the level of the crime. For example, for breach of trust, the period is in units of four months with a maximum of one year.
In Japan, except for arrest "while crime is ablaze," investigating authorities cannot hold suspects in custody based solely on their own decisions. That means, the equivalent of "garde à vue" doesn't exist. Nevertheless, French media have interpreted "arrests" in Japan as "garde à vue" because it happens at the investigation stage. Some writers have even misused the term when referring to detention of a suspect in Japan.
Ghosn was detained for about 130 days, a period that was widely criticized as being too long. However, it is not longer than detention in France. According to one study, the average detention in France lasts 266 days, with a median value of 229 days . Criticism was also heard about bail conditions in Japan that did not allow Ghosn to meet freely with his wife. They were sometimes described as inhumane. Yet preventing the destruction of evidence is also a ground for detention in France, and prohibition of contact with a specific person is included in the compliance rules there.
Japan has a conviction rate that exceeds 99%. This has caused many people to conclude that the principle of presumption of innocence is not working or that a fair trial cannot be anticipated in Japan.
In Japan, investigations are carried out by administrative agencies - namely police officials and prosecutors. At the time of indictment, the prosecution's evidence is not presented to the court. The accused is also not required to offer proof of innocence. It is the duty of the prosecution to offer evidence that the defendant committed the crime charged and to convince the fact-finder, beyond a reasonable doubt, that the defendant is guilty. If the prosecutor fails to provide proof beyond a reasonable doubt, the accused is, naturally, found not guilty. Japanese trial proceedings are conducted in compliance with those rules of the burden of proof: the presumption of innocence. The pretrial detention of a suspect or defendant, however, is irrelevant to that principle. Furthermore, it goes without saying that the various disadvantages borne by the suspect or defendant due to detention are not "punishment."
In France too, the principle of presumption of innocence is described as a rule that imposes the burden of proof on the prosecutor. If the court is not convinced that the accused is guilty, the judgement must be "in doubt, for the accused (in dubio pro reo)." However, French criminal proceedings are designed so that the judge/court plays central role in finding the truth. In serious cases or complicated economic cases, a preliminary examination is conducted by an investigating judge. If a formal trial is deemed necessary, the case will be referred to a trial court.
Trial proceedings begin with the presiding judge, who has examined the dossier of the case, informing the accused of the charged facts. Perhaps because of such a procedural structure, an amendment to the Code of Criminal Procedure in 2000 added a preamble to strengthen the principle of the presumption of innocence. This preamble states, "Suspects and accused individuals are presumed to be innocent until proven to be guilty. Acts violating this presumption are prevented in accordance with law, and the damage caused by such violations shall be restituted." And the Civil Code provides for an injunction etc. against acts such as media reporting that presents a suspect or accused as guilty. Based on his awareness of such provisions in French law, it is understandable that Ghosn surmised that the Japanese prosecutors leaked information, and that his belief that the deck had been stacked led him to profess innocence at a press conference. Nevertheless, the principle of presumption of innocence in Japan was in effect and would have been applied in the trial.
The conviction rate in France is about 93% to 94%. This is lower than in Japan. However, it is neither logical nor scientific to use these numbers as a basis for stating that the principle of presumption of innocence functions in France but fails to function in Japan. In Japan, about 60% of the cases that go to prosecutors are not indicted. More than 20% of the cases are tried by summary procedures. Ultimately, only about 8% of the cases go to trial. The high conviction rate in Japan may be a result of prosecutors only pursuing those cases in which they believe the accused can be proven guilty based on sufficient evidence. The high conviction rate itself is not a synonym for an unfair trial.