A glitch in the popular Google Docs service resulted in users getting locked out of their documents on Tuesday because, according to a message, they had violated the company’s terms of service. The issue has now been fixed, but the incident is raising some uncomfortable questions for Google.
The glitch gained widespread attention yesterday when Rachael Bale, a National Geographic journalist, tweeted that Google had “frozen” her document while she was writing a story about wildlife crime. Others also claimed to be abruptly cut off from Google Docs, which provides a suite of services similar to Microsoft Office.
The incidents amounted created inconvenience as many users rely on the cloud-based Google Docs to access information about both their personal and professional lives. In response, a Google employee explained in an online forum that “a code push … incorrectly flagged a small percentage of Google Docs as abusive, which caused those documents to be automatically blocked.”
While the company has since cleared up the problem, the episode has proved unsettling for some Google Docs users, including Bale, who tweeted “this kind of monitoring is kind of creepy.” Others expressed similar sentiments:
The concern is especially relevant for those who use Google’s tools to record sensitive information. Indeed, in a conversation I had last week with journalists at a well-known newspaper, reporters there expressed unease that Google might not just freeze their files, but use its omniscient view to identify their sources.
Such fears are hardly new, however, given that Google has long been able to “read” the contents of individuals’ Gmail accounts. And as the company has explained repeatedly in the case of Gmail, such “reading” is entirely automated and is used only to identify keywords for advertising purposes.
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This week’s Google Docs incident amounts to a similar situation: No individual at Google decided to freeze Bale’s document based on what she was writing. Instead, she appears to have typed something that set off an automated tripwire, which has since been lifted.
Still, all of this raises the question of what Google can and can’t do when it comes to spying on its users’ activities. As of now, Google sets the rules in its terms of service, which explain that its “automated systems analyze this information as it is sent and received.”
The Washington Post pressed Google for more context on what exactly this means, and obtained the following details:
Google said that it does not technically read files, but instead uses an automated system of pattern matching to scan for indicators of abuse. Though it can identify clusters of data that might suggest a violation, the system does not pull meaning from the content, according to a company spokesperson.
The bottom line is that the company is relying on the fact its scanning systems are automated to ensure no significant invasions of privacy take place. This might provide some comfort to Google users but also raises the question of whether non-automated scanning ever takes place too—and whether anyone will ever know if it does.
Fortune contacted Google for further comment and will update as needed.