Amazon is restricting reviews of James Comey’s new book, A Higher Loyalty, likely in an effort to limit politically-motivated negative reviews of the book from supporters of President Donald Trump, whom Comey criticizes extensively in the book.
The restrictions were originally spotted by Deadline, which reports reviews are restricted to only “verified buyers” of the book. When Fortune attempted to post a review through an Amazon account that hadn’t purchased the book, we received the following message:
“This product currently has limitations on submitting reviews. This may be because we detected unusual review behavior on this product, or to maintain the best possible shopping experience.”
In a statement, Amazon seemed to confirm Deadline’s assessment, saying: “We never reject reviews based on star rating or sentiment. When numerous reviews post in a short amount of time that are unrelated to the product, we suppress all non-Amazon Verified Purchase (AVP) reviews. Reviews are meant to help customers by providing real feedback on a product from other customers who have tried it.”
Comey was fired as FBI Director by Trump just under one year ago, on May 7th of 2017. That firing set in motion events leading to the appointment of Special Counsel Robert Mueller just ten days later.
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Since his firing, Comey has become increasingly vocal in his criticisms of the President. In his new book, which has become a massive bestseller, Comey compares Trump to mob underboss Sammy “The Bull” Gravano, and says the President is “untethered to the truth.” Reviews successfully posted to the book’s Amazon page are almost uniformly glowing, with 89% of them giving Comey’s book five stars at this writing.
Trump has had his own harsh words for Amazon owner Jeff Bezos, criticizing Amazon’s business practices, accusing Amazon of underpaying the Post Office for shipping, and, of course, constantly dismissing the Bezos-owned Washington Post as “fake news.”
Politically contentious books have in the past attracted harshly negative reviews, many likely from reviewers who never purchased or read the book in question. In another recent example, Amazon apparently chose to delete hundreds of negative reviews of Hillary Clinton’s book What Happened, mostly from reviewers without verified purchases.
Fortune has reached out to Amazon to determine the precise nature of the restrictions on Comey’s book, and will update with any further information.
Update 4/24/18: This story has been updated with a statement from Amazon.