Sex robots are rapidly becoming a part of the national conversation about the future of sex and relationships, writes Francis X. Shen, an expert in artificial intelligence, neuroscience, and law at the University of Minnesota.

A 2017 survey found that almost half of Americans think that having sex with robots will become a common practice within 50 years.

But Shen argues the United States' legal system has numerous blind spots concerning sex robots.

From defining what sex robots are to measuring their safety, America is unprepared for a market for sex robots.

The robots are here. Are the "sexbots" close behind?

Amid reports from the Drudge Report to The New York Times, sex robots are rapidly becoming a part of the national conversation about the future of sex and relationships. Behind the headlines, a number of companies are developing robots designed to provide humans with companionship and sexual pleasure — with a few already on the market.

Unlike sex toys and dolls, which are typically sold in off-the-radar shops and hidden in closets, sexbots may become mainstream. A 2017 survey suggested almost half of Americans think that having sex with robots will become a common practice within 50 years.

Various styles and designs of sex dolls at the WMDOLL factory in Zhongshan, China. Aly Song/Reuters

As a scholar of artificial intelligence, neuroscience and the law, I'm interested in the legal and policy questions that sex robots pose. How do we ensure they are safe? How will intimacy with a sex robot affect the human brain? Would sex with a childlike robot be ethical? And what exactly is a sexbot anyway?

There's a problem defining what a 'sex robot' is

There is no universally accepted definition of "sex robot." This may not seem important, but it's actually a serious problem for any proposal to govern — or ban — them.

The primary conundrum is how to distinguish between a sex robot and a "sexy robot." Just because a robot is attractive to a human and can provide sexual gratification, does it deserve the label "sex robot"?

It's tempting to define them as legislatures do sex toys, by focusing on their primary use. In Alabama, the only state that still has an outright ban on the sale of sex toys, the government targets devices "primarily for the stimulation of human genital organs."

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The problem with applying this definition to sex robots is that they increasingly provide much more than sex. Sex robots are not just dolls with a microchip. They use self-learning algorithms to engage their partner's emotions.

The Mark 1 robot was built by Ricky Ma, a product and graphic designer. Bobby Yip/Reuters

Consider the "Mark 1" robot, which resembles the actor Scarlett Johansson. It is regularly labeled a sex robot, yet when I interviewed its creator, Ricky Ma Tsz Hang, he was quick to clarify that Mark 1 is not intended to be a sex robot. Rather, such robots will aim to assist with all sorts of tasks, from preparing a child's lunch to keeping an elderly relative company.

Humans, of course, can navigate both sexual and nonsexual contexts adeptly. What if a robot can do the same? How do we conceptualize and govern a robot that can switch from "play with kids" mode during the day to "play with adults" mode at night?

There are thorny legal issues with the 'types' of robots allowed

In a landmark 2003 case, Lawrence v. Texas, the Supreme Court struck down Texas' sodomy law and established what some scholars have described as a right to sexual privacy.

There is a split among circuit courts in how Lawrence should be applied to state restrictions on the sale of sex toys. So far, Alabama's ban has been upheld, but I suspect that all sex-toy bans will eventually be struck down. If so, it seems unlikely that states will be able to wholesale restrict sales of sex robots generally.

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Bans on childlike sex robots, however, may be different.

A worker taking a photo of a sex doll at the WMDOLL factory. Aly Song/Reuters

It is not clear whether anyone in the US already owns a childlike sex robot. But even the possibility of child sex robots prompted a bipartisan House bill, the Curbing Realistic Exploitative Electronic Pedophilic Robots Act, or CREEPER. Introduced in 2017, it passed unanimously six months later.

State politicians will surely follow suit, and we are likely to see many attempts to ban childlike sex robots. But it's unclear if such bans will survive constitutional challenges.

On one hand, the Supreme Court has held that prohibitions on child pornography do not violate the First Amendment because the state has a compelling interest in curtailing the effects of child pornography on the children portrayed. Yet the Supreme Court has also held that the Child Pornography Prevention Act of 1996 was overly broad in its attempt to prohibit "child pornography that does not depict an actual child."

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Childlike sex robots are robots, not humans. Like virtual child pornography, the development of a childlike sex robot does not require interaction with any children. Yet it might also be argued that childlike sex robots would have serious detrimental effects that compel state action.

Perhaps someday sex robots will become sentient. But for now, they are products.