Government ministries and agencies rejected 11.4 percent of requests for information in fiscal 2001, according to government data.
The Public Management, Home Affairs, Posts and Telecommunications Ministry said that 48,636 requests were filed in the year following the introduction of the freedom of information law in April 2001.
Of the 44,734 requests on which decisions were made, information was disclosed in full in 25,119 cases, partly disclosed in 14,534 cases and not disclosed in 5,081 cases, according to the ministry.
In 16,409 requests in which information was withheld, the reason given was that disclosure would lead to particular individuals being identified.
The pertinent documents could not be found in 3,151 cases, while in 278 cases, agencies were not allowed to say whether the documents, such as criminal records, existed.
The Foreign Ministry, which was hit by a series of corruption scandals involving its officials, received 2,233 requests for information. It turned down 867, the most among any government entity.
There were 1,354 petitions seeking to reverse decisions not to disclose information, 180 of which had final decisions given by the end of March.
Fourteen cases were taken to court.
Of the three cases that have received a lower-court ruling, one decision not to disclose requested information was overturned.
The National Tax Agency received the largest number of disclosure requests at 19,296, followed by the Land, Infrastructure and Transport Ministry at 5,129 and the Health, Labor and Welfare Ministry at 3,818.