Why is "highlighting in black" considered a poor method for redaction?

Highlighting in black as a method for redaction is regarded as poor practice because it does not effectively protect sensitive information. When text is highlighted in black, it can obscure the information from casual viewing, but this does not prevent the underlying text from being recovered or seen with certain techniques. For instance, if the document is converted to a different format or manipulated using software, the original text may become visible again.

Furthermore, highlighting in black does not prevent the information from being copied. If someone selects the highlighted area and pastes it elsewhere, or if they have the capability to view the source document, they can retrieve the hidden information, which is particularly concerning for confidential or sensitive data.

Additionally, sharing documents with black highlighting online poses a risk, as individuals may use various tools to extract or unearth the originally obscured text, thereby exposing the sensitive information.

Given these considerations, it becomes clear that relying on highlighting in black does not provide the robust protection necessary for redaction, confirming that all these issues contribute to categorizing this method as inadequate.