Amazon is ready to let people develop their own Alexa apps, getting its customers to create games, lectures, and other voice-controlled experiences that can expand what its virtual assistant can do.

There will be limits, however. Alexa cannot be trained to spout hate speech or other derogatory content, including Nazi propaganda. Preventing Alexa from becoming a Nazi robot seems wise. Yet, customers in the market for racist, white supremacist content can find plenty for sale in Amazon’s book section.

Making decisions on the nature of content is inevitably somewhat arbitrary, and many tech giants have struggled with it. Amazon’s approach has been to patrol only certain sections of its sprawling business, leading to the somewhat paradoxical result of barring, say, a T-shirt emblazoned with a Nazi swastika, while selling a book promoting Nazi theories.

With hate crimes in the US on the rise, activists fighting against hate speech say Amazon should do better, given its massive reach.

Arbitrary policing

It’s not that Amazon doesn’t police anything. The company has detailed terms of service prohibiting hate speech. They do not allow, for instance, products that promote, incite or glorify hatred, violence, racial, sexual or religious intolerance or promote organizations with such views. “We’ll also remove listings that graphically portray violence or victims of violence,” Amazon’s terms say. Yet these terms “apply to all products except books, music, video and DVD,” arguably the categories most likely to include such content.

Other tech companies that handle content also follow rules that might seem perplexing. Facebook, for instance, which employs 15,000 people to moderate content, banned white supremacy while allowing white nationalism (though it’s reviewing its position on the issue).

When contacted for this story, Amazon offered no insight about why it has different rules for different parts of its business, but referred Quartz to its content guidelines for books. It specifically pointed to the portion stating that “as a bookseller, we provide our customers with access to a variety of viewpoints, including books that some customers may find objectionable.”

“A Christian must oppose beliefs and actions of Jews that result from their rejection of Christ,” says one customer review.

The same guidelines note that Amazon “reserve[s] the right not to sell certain content, such as pornography or other inappropriate content”—though when requested, the company didn’t provide details of what it deems “inappropriate content.”

One publication that made the cut: The manifesto by the White Rabbit Three Percent Illinois Patriot Freedom Fighters Militia, a hate group responsible for bombing a mosque in Minnesota. It’s just one of the episodes that prompted calls for Amazon to get rid of hateful publications. The manifesto is still on the site, where it sells for $6.75.

Also available is The Turner Diaries, a 1978 novel by neo-Nazi leader William Luther Pierce that has inspired extremists from Oklahoma City bomber Timothy McVeigh to Idaho domestic terrorist group The Order, according to the FBI. The story portrays the violent overthrow of the US government, beginning with the bombing of FBI headquarters in Washington, DC. The Turner Diaries, which is banned in Germany, has been reviewed 353 times on Amazon, with an average rating of 3.7 out of 5 stars.

Indeed, a surprisingly extensive selection of white nationalist and neo-Nazi titles are still sold on Amazon’s website, long after they were exposed by activists.

Racist material

Amazon sells items promoting hate through three different channels: There are sales made directly by Amazon, sales made by third-party sellers on Amazon, and materials—particularly books—created by extremists using the self-publishing space offered by Amazon.

The platform has several books on offer by the late George Lincoln Rockwell, a Holocaust denier and the founder of the American Nazi Party. Rockwell’s 1966 tract, White Power, sells for $13.95 in paperback, $24.99 in hardcover, and $6.45 for the Kindle version.

One “verified purchaser” of White Power gave the book a 5-star review, writing that “the Jews” employ “psychological devices to bring about the complete destruction of a once honorable people,” namely whites, and added, “Anybody who has the European spirit flowing through their veins should read this book…Show the world that there is nothing wrong with loving the white race and embracing its inherent power.”

Seventy-eight people “found this helpful,” according to Amazon’s site.

Amazon description: “The last and most powerful book written by the founder of the American Nazi Party, George Lincoln Rockwell.”

In White Identity by Jared Taylor, a white supremacist who has earned a place in the Southern Poverty Law Center’s “Extremist Files,” warns white readers that “if they do not defend their interests they will be marginalized by groups that do not hesitate to assert themselves, numerically and culturally.” The 2011 book, which gets 4.6 stars on Amazon from 131 customer reviews, qualifies for free shipping on orders over $25. Gift wrapping is available.

The list goes on. Amazon sells the Kindle version of the White Power Manifesto by Andrew B. Aames, a registered sex offender who penned a 2015 memoir about his legal woes, for just $0.99. Greg Johnson’s White Nationalist Manifesto, in which he argues for “the right of all white peoples to self-determination,” is also in stock. Amazon also carries Jason Köhne’s Born Guilty, in which the author “recounts his extraordinary struggle under the physical and psychological abuse of a society obsessed with an anti-white ideology,” according to the publisher. It has been name-checked on Twitter by former Ku Klux Klan grand wizard David Duke.

Self-policing content

Unlike many European countries, which bar the publication and sale of material promoting hate, the US has no laws that forbid Amazon from selling any of the books above.

The company has the right to decide what products it does and does not sell. The only thing keeping it from offering racist material is its goodwill or public pressure, which has been growing.

Last year, the Action Center on Race and the Economy and the Partnership for Working Families, a group that produces research to promote race equality, published a report accusing Amazon of giving hate groups a platform to “generate revenue, propagate their ideas, and grow their movements.”

“Amazon must take a public stand against hate and violence, and take action to ensure that it is not profiting from hate or enabling others to profit from hate,” said the report.

Amazon, like many other major tech companies, has attempted to reassure its customers that it is on the lookout for hate speech, says Jared Holt of Right Wing Watch, a Washington, DC nonprofit that monitors the extreme right. However, it hasn’t implemented the necessary changes to its systems required to flag and remove hateful content, he adds.

“Glad someone would stand for truth and loved his race like others do,” says one of 42 customer reviews on Amazon.

Bad for business

One incentive for more effective self-policing is that selling racist material can put off a lot of customers.

“It’s disturbing, it’s distressing. You don’t want your kids to come across it,” says Mark Pitcavage, a senior research fellow with the Center on Extremism at the Anti-Defamation League.

Many other online sellers have recognized this, says Pitcavage, pointing to eBay as an example. The company has been policing hate materials for many years, and though things inevitably fall through the cracks, he has noticed a very significant difference in the availability of products inciting hate before and after eBay’s policy against them.

Similar examples could be found prior to the advent of internet shopping, Pitcavage says. Record stores, for instance, would often refuse to carry white supremacist albums, and bookshops or even libraries would rarely carry items promoting hate speech.

No clean fix

It’s hard to make the case that Amazon has a duty to ban certain content from its US site, because free speech is at the core of American values.

“I don’t know that there is a clean fix,” says Holt of Right Wing Watch.

For example, Shannon Martinez, a former neo-Nazi who now works to extricate others from hate groups, calls the idea of banning books outright “highly problematic,” because it could set a bad precedent for restricting other kinds of speech.

Even if Amazon were to ban racist or Nazi books, what criteria would be acceptable? One might be the threat posed by the books. While some of them may not be a direct call to violence, some come close to crossing the line, says Martinez.

Still, she questions whether Amazon should be giving people such easy access to certain materials. Short of actually pulling racist titles from its virtual shelves, Martinez believes Amazon should modify its recommendation engine so it no longer suggests long lists of other problematic books to people who search for a racist title.

Spoiled for choice.

Right now, Amazon links to an extensive stock of similar extremist material, says Martinez. “If I’m a 19-year-old kid who heard [white nationalist] Richard Spencer mention the title of a particular book and I go to Amazon to look for it, then I have direct access to an entire world of extreme right-wing literature at my fingertips,” she adds.