Nothing could be more reliable as precedent than an opinion of the United States Supreme Court, issued earlier in the day. Yet even that could change.

The New York Times gives examples of justices altering the wording of published opinions, sometimes in ways that are legally significant, hours, days, or even years after the opinions were first issued. Sometimes the unrevised opinion remains available on respected sites for legal research. Fortunately, the Court is now making the changes more transparent, but it remains to be seen whether, or how quickly various websites will ensure that they have the current version.

Chalk it up as just one more reason lawyers need to update their legal research from a reliable and current source.