A report into drug arrests at ports of entry along the U.S.-Mexican border over the past five years has cast doubt on the effectiveness of one of the Trump administration's policies.
A study published by Addictions.com suggests that ports of entry are one of the main avenues for drug smuggling, indicating that a border wall would not be able to prevent all drugs from entering the country, AZ Central reported.
Six of the top 10 ports of entry for drug-related arrests over the past five years were in Arizona, according to data scientist Logan Freedman, who prepared the report.
"A majority of these drug arrests are going to be large quantities of drugs," Freedman explained, according to AZ Central. "So if someone was captured in, say, New York City with under an ounce of marijuana, it's not necessarily going to show up in this report, because it's going to be misdemeanor crime. This is going to be large drugs coming into the U.S."
In April, Trump urged Congress to approve funding for the wall in order to clamp down on the drugs trade.
"The wall is a very important tool in stopping drugs from pouring into our country and poisoning our youth (and many others)!" Trump tweeted, according to The Hill.
He went on to argue that if the wall was not built, "the drug situation will never be fixed the way it should be!"
Earlier in April, Attorney General Jeff Sessions toured the border to make the case for the wall. He declared that it would help cities clear up the "filth" brought in by drug cartels.
"The barrier, the wall, will have a great and positive impact and will continue our ability to follow through on a commitment to end the lawlessness," Sessions added, according to NBC News.
Critics have argued that the resources required to build the wall could take funds away from other drug enforcement agencies.
Experts have also pointed to the use of waterways by smugglers, a threat which the government has also admitted.
"Part of the reason that drugs come through waterways is because they're looking for other ways around where we have good defenses," David Lapan, a spokesman for the Department of Homeland Security, said, according to CNN.
Statistics from Customs and Border Protection show that drug seizures at ports of entry are spread relatively evenly along the Mexican border, with California leading the way.
Seizures of marijuana have dropped, while more potent drugs like heroin and meth are on the increase.
The Tucson sector, which covers most of the Arizona border, was responsible for seizing 60 percent of all drug seizures not made at ports of entry.