It's one of the more incendiary questions discussed in wildlife conservation circles: Should there be a legal trade in elephant ivory?

This debate has been waxing and waning since at least 1989, when the Convention on International Trade in Endangered Species (CITES) voted to "ban" the international trade in ivory after a ferocious wave of poaching in Africa that left hundreds of thousands of elephants butchered.

Some conservationists say that a limited legal ivory trade is needed to satiate demand, especially in China, in a controlled manner.

Many others argue that the 1989 ban must be kept in place to protect elephants, especially now that poaching has once again risen to catastrophic levels. One hundred thousand elephants were slaughtered from 2010 through 2012, according to a study published in the August 19 issue of the Proceedings of the National Academy of Sciences. A legal trade, they say, would only lead to even greater demand for ivory.

Elizabeth Bennett, a longtime conservationist and vice president for species conservation at the Wildlife Conservation Society (WCS), says it has become clear that it is impossible to have a controlled trade in elephant ivory.

That was her conclusion in a recent essay she wrote in the scientific journal Conservation Biology. In an interview, Bennett says she examined the prospect for a legal market in ivory and concluded that because corruption in some countries among certain government officials is so pervasive, "it can't be done."

The corruption, Bennett wrote, is specifically "among government officials charged with implementing wildlife-related legislation." These corrupt activities include "officials demanding bribes for compliance ... and accepting bribes to overlook illegal activities," or "to switch or alter CITES or other permits along the trade chain so that, through fraudulent paperwork, an illegal item seems legal."

In an interview, Bennett says she wrote the piece for two reasons: "We had a great increase in the poaching of elephants and data showing the effect of poaching. And then we also still had countries advocating for mechanisms to trade in ivory."

These countries, she says, include South Africa, which will host the next CITES conference in 2016, and China. Bennett's study notes that the global illegal trade in ivory has doubled since 2007.

Why is corruption rife? "There are two components to why the corruption happens: poorly paid officials and highly financed criminal networks," Bennett says. "That's a bad combination."

The overarching problem is that "once illegal ivory has entered the legal trade, it's difficult or impossible for enforcement officers to know what's legal and illegal."

Cleaning up corruption throughout an ivory trade network that permeates countries across the globe would take decades. At current poaching levels, the African elephant doesn't have that kind of time.

It is unclear how many elephants are left in Africa. A 2007 report gave a range of 472,000 to 690,000, but the actual number may well be as low as 250,000.

View Images An undercover ranger detusks a bull elephant killed by a spear near Kenya's Amboseli National Park in 2011. Photograph by Brent Stirton, Getty Images/National Geographic

Not Quite a Global Trade Ban

Other flashpoints of discussion have been ignited by CITES-approved ivory auctions, called "one-off ivory sales." The sales, in which stockpiled ivory was auctioned to designated trading partners, took place in 1999 and 2008.

In the first sale, ivory from Botswana, Namibia, and Zimbabwe was auctioned to Japan. The sale, according to CITES, represented 5,446 tusks and earned $5 million, which was used for "elephant conservation activities."

In the second sale, ivory from those countries and South Africa was sold to accredited

Chinese and Japanese traders. "Over 15 million USD for African elephant conservation and local communities have been raised through the sales of 102 tonnes of stockpiled ivory," according to a CITES press release.

To some conservationists, these sales were disastrous, spurring the current poaching frenzy by keeping the markets active, confusing consumers as to what was legal versus illegal ivory, and offering a loophole for laundering illegal ivory into markets. To others, the correlation is unproven.

View Images VIRGINIA W. MASON, NG STAFF SOURCES: WILDLIFE CONSERVATION SOCIETY; C4ADS; AFRICAN ELEPHANT SPECIALIST GROUP, IUCN; NATIONAL GEOSPATIAL INTELLIGENCE AGENCY; EC JOINT RESEARCH CENTRE

The World Wildlife Fund (WWF), for example, supported the 2008 sale. Bennett says the WCS took no official stand. "We were more open-minded about a legal trade until the last three or four years," she says. "But the levels of corruption now prove we cannot control the trade."

Debate in the U.S.

Bennett's paper was released in the midst of a debate in the U.S. about its own domestic ivory trade. In February, the Obama administration announced its National Strategy for Combating Wildlife Trafficking, which was created to address "the global wildlife trafficking crisis."

In addition, the White House announced a ban on the commercial trade of elephant ivory—on "imports, exports and domestic sale of ivory, with a very limited number of exceptions." The U.S. Fish and Wildlife Service (FWS) is working to implement the ban.

The ban has been unwelcome to some, including the National Rifle Association (NRA), the U.S.'s most powerful gun lobby. The NRA calls the ban on ivory an "overreach of authority" and problematic because "any firearm, firearm accessory, or knife that contains ivory, no matter how big or small, would not be able to be sold in the United States, unless it is more than 100 years old."

Trophy hunters are still allowed to hunt elephants in Africa for their parts, but the ban sets limits on the number of trophies that can be imported. The NRA also protests the ban because of those limits. (See: "Controversy Swirls Around the Recent U.S. Suspension of Sport-Hunted Elephant Trophies.")

In July, Republican Senator Lamar Alexander of Tennessee introduced a bill into the Senate called the Lawful Ivory Protection Act of 2014; Republican Representative Steve Daines of Montana introduced the same bill to the House of Representatives. These bills have the support of the NRA because they "protect firearms owners and sportsmen from a federal ban on the sale and trade of objects containing lawfully-imported elephant ivory." (Both bills have been forwarded to committees.)

Meanwhile, New York and New Jersey recently passed state bans on selling or importing ivory.

Colman O Criodain, the wildlife trade policy analyst at the WWF, says his organization mostly agrees with Bennett that any legal trade should be stopped.

View Images Large, intricate ivory carvings sell for hundreds of thousands of dollars in China, where demand has increased in recent years. Photograph by Brent Stirton, Getty Images/National Geographic

O Criodain admits that the 2008 one-off sale "didn't work out the way we at WWF expected. So we wouldn't automatically endorse a future ivory trade regime." The FWS notes on its website, "Today, given the current poaching crisis and the scale of illegal trade, it's unlikely that the United States would be able to support a one-off sale."

O Criodain says the problem with the 2008 sale is that China's government controlled the purchase of the ivory, releasing it into the trade at an inflated price. This encouraged carvers to source their ivory illegally.

In addition, the number of retail outlets permitted to sell ivory increased without a commensurate increase in enforcement effort. This led to abuses—illegal outlets operating without permits and accredited outlets mixing illegal ivory with legal.

In theory, O Criodain says, there could be a legal international trade in ivory, "but in practice it's very difficult, and we've seen from the experience of the one-off sales it's proven difficult to manage." He believes that any efforts by countries like South Africa to launch a trade—if it chooses to at the next CITES conference—wouldn't have a "hope in hell."

Plus, "if there were to be further sales," O Criodain says, "we'd have to impose even more conditions on the purchasing countries in order to be reassured beyond reasonable doubt that the sale might not facilitate laundering of illegal ivory. And some countries might take the view that we're being overly prescriptive. So I have doubts about the practicalities of another one-off sale."

But, he adds, "the issue isn't as simple as legal versus illegal. Most of what is being transited is illegal. The reason some organizations now want the legal ivory trade—including antique ivory—curtailed is that they see it as a risk for laundering new ivory. And they believe if Western countries—like the U.S.—give up their ivory trade, it would put pressure on Thailand and China to do the same." (Thailand is currently under fire by CITES for operating as both a transit country and for its unregulated domestic ivory market.)

View Images Top left: A number of Chinese nationals were caught with ivory and other illegal wildlife contraband in their personal suitcases when leaving Kenya in 2011. Top right and bottom left: Ivory figurines and jewelry were part of an estimated six tons of confiscated ivory crushed in 2013 by the U.S. Fish and Wildlife Service. Bottom right: These ivory tusks were seized by customs officials in Hong Kong in 2013. From left to right: Photographs by Brent Stirton, Getty Images/National Geographic; Joe Amon, The Denver Post/Getty; Doug Pensinger, Getty; Bobby Yip, Reuters

Trade Watchdog

One of the most aggressive groups monitoring the illegal trade in ivory is the London-headquartered Environmental Investigation Agency (EIA).

"Looking back 25 years, EIA has done more investigations into the illegal ivory trade than any other group in the world," says Allan Thornton, the organization's cofounder.

In 2010, Tanzania and Zambia submitted proposals to CITES to sell their ivory stockpiles by downlisting their elephants from Appendix I (maximum protection) to Appendix II (lesser protection). EIA's undercover work, written up in a report, "Open Season: The Burgeoning Illegal Ivory Trade in Tanzania and Zambia," provided strong evidence of an illegal ivory trade between Zambia and China and played a significant role in the defeat of Zambia's proposal.

EIA lobbied against the one-off sales in 1999 and 2008. "All evidence," Thornton says, "shows ivory trade is incompatible with the conservation of elephants."

He believes that bans on trade can reverse a poaching trend. "In the run-up to the 1989 ban, pro-trade groups said that it won't work, and literally within a few months of it passing, the global ivory trade collapsed. Poaching dropped overnight."

Thornton added, "I've been doing environmental work for 38 years. I've never seen such an abrupt change in any environmental issue I worked on."

The 1989 CITES global trade ban was "dismantled" by the one-off sales, which "substantially compromised its integrity, effectiveness, and enforceability," he argues.

"Japan is back in the ivory business. China has probably taken the market that the EU and the U.S. once had. The trade is back. There's a legal trade that helps the illegal trade to happen on an industrial scale. All the permits and tricks are still there. And this is the crux of everything: What's happening now is what was happening in 1988."

View Images About five tons of trafficked ivory were burned in Kenya in 2011, but many more tons remained stockpiled. Photograph by Brent Stirton, Getty Images/National Geographic

Corruption Not the Main Culprit

Phyllis Lee, chair of the Scientific Advisory Committee for the Amboseli Trust for Elephants, in Kenya, agrees with Bennett that corruption is a problem in the ivory trade.

"[Bennett's] sensible arguments are in part based on what's known about why trade in wildlife so often results in extinction scenarios. Corruption is a problem that enables illegal activities—poaching, transport of contraband, transborder shipment of contraband—and the current trade in ivory is primarily illegal."

But, Lee adds, "corruption merely contributes to the lack of policing of others' extractive actions on a so-called resource."

Take whaling, she says. Some whale species have been brought to the edge of extinction because of the lack of international controls on hunting quotas and poor policing of the seas—not necessarily because of corruption.

Furthermore, agreement on the best policies to avoid extinctions don't even exist in conservation circles. "That's CITES's job," Lee says, implying its failure.

When asked why, after all these years, wildlife organizations and trade nations still haven't reached a consensus about how to protect elephants, Lee answers bluntly: "Greed. Self-interest. And a lack of the ethical appreciation and understanding of elephants."

A Pro-Trade "Outlier"

According to Bennett, the trade debate in the conservation community is becoming "more one-sided" against allowing a trade. But there are those who communicate a pro-trade stance.

Daniel Stiles, who lives in Kenya and has long studied the ivory trade markets in Asia and Africa, is a member of the International Union for Conservation of Nature's African Elephant Specialist Group (AfESG). The group provides CITES with scientific information.

Stiles says that his opinions don't necessarily reflect those of the AfESG, and he acknowledges that he's now considered an "outlier" for his pro-trade stance.

Stiles maintains that wildlife conservation organizations often—wrongly—advocate against a regulated raw ivory trade because those groups are often made up of "zoologists or scientists studying elephants who don't understand how trade systems work."

He adds, "They don't understand the basic economic principles of supply and demand. When demand for a scarce, valuable commodity is high, the worst thing one can do is shut off supply. That makes the commodity soar in value. In the case of ivory, this has been disastrous for elephants."

Stiles, who's trained as an anthropologist, supports an international ban on worked ivory, but he advocates for a limited legal trade with China in raw ivory. (He also believes the domestic trade in some countries, such as Thailand, should be shut down.)

View Images A Maasai tribesman gently holds the tusk of a tranquilized wild elephant during an radio-collaring operation in southern Kenya in 2013. Photograph by Ben Curtis, AP

He says that there's a difference between China's raw ivory market and the worked ivory market: The two have different buyers, trade chains, and demand drivers.

With worked ivory, Stiles says, "the buyers are consumers, at the end of the trade chain. They buy ivory to give as gifts, for esthetics, culture, or social prestige."

He says the problem is that most of the worked ivory in China "is probably derived from poached elephants, and almost all of the worked ivory in Southeast Asia is illegal."

According to Stiles, a successful legal trade would mean that the worked ivory consumers buy would be derived from a legal source.

In Stiles's opinion, a successful legal raw ivory trade would look like this: The ivory would come from closely monitored African ivory stockpiles. The tusks in those piles would come from elephants who died naturally or were shot because they were "problem animals." (He's opposed to culling wild elephants to augment stockpiles.) That ivory would be sent directly to purchasers in China.

The ivory would get to China not via another one-off sale (he says the last one has "caused a real mess"), but "through annual or semiannual auctions. I think if 50 tons of legal ivory could be supplied to China annually, the poaching rates would crash."

He also believes that a robust supply of legal ivory would eliminate ivory speculators, who he thinks have been driving the increased poaching since 2007. (See: "A Young Chinese Conservationist Discusses His Country's Role in the Ivory Trade.")

"Prices have shot up so much since 2008, when CITES shut off any chance of more legal ivory, that speculators have started stockpiling tusks to sell at a later date at great profit. They are assuming that no legal ivory will appear on the market and that ivory will continue to get scarcer (poaching and stockpile destruction), thus driving the price of ivory ever higher. I believe it is the speculator that is driving the increased poaching since 2007-8," he wrote in an email.

Stiles concludes: "The only reason I don't agree with closing the market in China is because a very large, well-established black market is in operation. So if a ban is implemented, it won't affect the black market—and might even make it grow."

Bryan Christy, author of National Geographic magazine's October 2012 "Ivory Worship" story, responds: "This is exactly what was argued to allow the 2008 ivory sale to China and Japan. The result has not been a well-regulated international ivory market. The result has been record killing of elephants."

Christy cites a recent Chinese criminal conviction of a government-authorized ivory dealer who smuggled more than seven tons of ivory through his shop to discredit the notion that legal and illegal ivory markets don't mix.

"Ivory is a fungible good," Christy says. "Imagine saying, 'The cocaine in this pile will be legal—the cocaine over here is not.'"

View Images A worker from an Asian elephant breeding center communes with a wild Asian elephant in Wild Elephant Valley, in China's Yunnan Province, in 2014. China has a strict elephant protection law, but large amounts of ivory enter the country illegally from Africa. Photograph by Jia daitengfei, Imaginechina/AP

"No Good Reason Why Anyone Needs Ivory"

Beth Allgood is among the many conservationists who disagree with Stiles. Allgood is the U.S. campaigns director for the International Fund for Animal Welfare (IFAW), which is lobbying for closure of the U.S. domestic ivory trade (with some very specific exemptions).

"Bennett's article clearly points out that poaching cannot be stopped in a corrupt world," Allgood says. "Trafficking cannot be stopped in a corrupt world, and buying cannot be stopped in a corrupt world." In her opinion, Bennett's essay slams the door shut on a viable legal ivory trade.

IFAW is an organization that promotes both the protection of a species and the welfare of individual animals.

So it's not surprising that a moral note sounds through Allgood's further argument: "Even if an international trade were sustainable, it doesn't mean it should take place. Ivory comes from a living, breathing being. You can't trade ivory as a commodity and not hurt an elephant. You can't make it in a factory. It's not like making widgets."

Moreover, "ivory isn't used for anything but art or ornaments. There's nothing that ivory is used for today that can't be replaced with something else," Allgood notes.

"In fact, there's no good reason why anyone needs ivory," she declares, "except elephants."