This week is Sunshine Week, an annual celebration of the right of historians, journalists and all Americans to access government information.

Perhaps the most important tool enabling Americans to ensure that their government is open and, therefore, accountable, is the Freedom of Information Act, a 52-year-old law that requires the federal government to release nonexempt information when it is requested. Even our most secret agency, the CIA, has provided online access to 13 million pages of historical records thanks to FOIA. Such documents are powerful and illuminating. For example, recent requests have revealed that the Interior Department awarded nearly 1,700 offshore drilling safety exemptions, gutting Obama administration safety rules put in place after the 2010 BP Deepwater Horizon ecological disaster. Others have proved that President Trump lied about the size of his inauguration crowd.

But despite FOIA’s power and importance, the administration of the law is deeply flawed. The government’s oldest pending FOIA request has been languishing for almost 25 years, and there are 111,334 FOIA requests waiting — a mountainous backlog. At many agencies, despite the law’s requirement for a response within 20 business days, FOIA requests are rarely processed within a year. Once processed, many requests are often unusable because of gratuitous redaction by agency censors. If anything, this problem is only getting worse. This week, the Associated Press reported that our government, “censored, withheld or said it couldn’t find records sought by citizens, journalists and others more often last year than at any point in the past decade.”

Inadequacies such as allowing for over-redaction and lengthy waits shaped FOIA legislation from the moment that the House Committee on Government Operations began studying the issue of executive-branch secrecy in 1955. And these failings matter. A government that so dismally follows the law requiring it to grant citizens access to information is a government that citizens can’t easily trust. And in such a system, officials may act with impunity, knowing that the public faces a steep climb to gain the information necessary to insist upon accountability.