Why redaction is all the rage
David Stevenson at 11:58 GMT on 25 November 2009
Redaction has been common in the legal profession for many years but the Freedom of Information Act and more open content sharing as a result of a web-connected world is driving the practice.
Before the MPs’ expenses scandal earlier this year, few people would have known the meaning of redaction. And then, only if you’d read media coverage in detail, would you know it’s using a white or black bar to hide sensitive information in a published document, for example an MP’s home address. Hiding text with a white or black bar serves two purposes – first to hide the sensitive text and second to indicate that text has been redacted.
Before electronic documents, a thick black marker or white-out liquid were used to redact paper documents prior to photocopying. For example, in most jurisdictions the identity of minors is protected under law. So a judgment in a case concerning a minor, which is a matter of public record, might be redacted to hide information that could help identify the child.
One of the drivers for redaction has been the legal right of citizens in countries that have Freedom of Information Acts (FOIA) to request information from public institutions. In the USA, the FOIA was signed into law by President Lyndon B. Johnson back in 1966. The Act allows for the full or partial disclosure of previously unreleased information and documents controlled by the United States Government. In 2000, the UK also passed a Freedom of Information Act that empowers citizens to request information from public bodies, who are required under law to respond. Germany has a similar law – the 2005 Federal Freedom of Information Act (Gesetz zur Regelung des Zugangs zu Informationen des Bundes), and many other EU countries have similar legislation in place.
The role of redaction in Freedom of Information is significant. Redaction makes possible the publication of information while protecting more sensitive data, the disclosure of which may compromise national security or place an individual in danger. I suspect that most redactions are made for more mundane reasons, but typically those disclosing information have to abide by a code of practice that is intended to prevent over-zealous use of the black marker.
PDF (Portable Document Format) files are a frequent target of redaction. They are often thought of as the electronic equivalent of paper, and the final form of a document that may have been authored electronically, scanned from an original, possibly assembled from a variety of sources. Governments and commercial organisations worldwide rely on PDF files for publishing documents on the web, putting them in the public domain or for delivering document-based information to third parties.
PDFs are preferred, particularly in the legal profession, because metadata (for example, evidence of past edits of the document) is stripped away during the process of conversion from the authoring format (such as a word processor) to PDF. Moreover they can be secured against casual changes while still permitting viewing and printing.
However, it’s vital that the tool used to redact a PDF not only obscures the text or graphics identified for redaction, but also removes the underlying data as well. There have been examples where redaction has failed, leaving the sensitive information in a form that can be recovered. In one case, a judgment issued by a US court was redacted in the word processor by the simple application of a black text background. As a printed document, it was redacted; the text was entirely obscured. But as an electronic document, all one had to do was swipe the text areas and copy to the clipboard, from where it could be pasted into a word processor.
With the demand for ever greater transparency from our public bodies, and the legal obligations of companies and other organisations, the requirement for redaction can only increase. Redaction, when used properly, is an important safeguard in today’s information-driven world that protects the innocent or vulnerable.



