After search results listed Nazism as the ideology of the California Republican Party, Google pointed the finger at Wikipedia. Wikimedia, the company behind Wikipedia, says "vandalism" is to blame. 

In a statement on Twitter late Thursday, Wikimedia explained how a link to Nazism appeared in Google search results for the California GOP.

"This vandalism was not visible to Wikipedia readers in the text of the article, and has been removed by volunteer editors," said Wikimedia in the statement. "The vast majority of things you read on Wikipedia are accurate, but some are not. Sometimes, information is out of date, needs a source, or is inaccurate due to simple vandalism."

Wikimedia added that usually problems like this are caught within minutes. 

This situation highlights some of automation's shortcomings. Google algorithmically pulls from high-profile sources -- Wikipedia, for example -- for general explanations and backgrounds. You've likely seen these highlighted areas on search results pages. And Wikipedia has been known to have its pages "vandalized," or edited to deliver a particular message or opinion. In this case, the two factors combined resulted in erroneous information showing up in the CAGOP search results on Google.

Google has systems in place designed to detect if information sources have been vandalized, but says occasionally errors get through. 

"This was not the result of any manual change by anyone at Google. We don't bias our search results toward any political party," said a Google spokesperson in an emailed statement. "Sometimes people vandalize public information sources, like Wikipedia, which can impact the information that appears in search. We have systems in place that catch vandalism before it impacts search results, but occasionally errors get through, and that's what happened here. This would have been fixed systematically once we processed the removal from Wikipedia, but when we noticed the vandalism we worked quickly to accelerate this process to remove the erroneous information."

First published on June 1, 7:44 a.m. PT.
Update, 9:24 a.m. PT: Adds statement from Google.

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