CBP is also in charge of the Container Security Initiative, which identifies and inspects foreign cargo in its mother country before it is to be imported into the United States.

In addition the CBP claims to have legal jurisdiction to conduct some activities up to 100 miles (160 km) inwards from any land or sea border.

In conjunction with the Department of State and the Bureau of the Census, CBP has put in place regulations that require submission of electronic export information on U.S.

CBP also works with the departments of state and defense to improve procedures on exported shipments of foreign military sales commodities.

[15] Responding to an urgent need for revenue following the American Revolutionary War, the First United States Congress passed, and President George Washington signed on July 4, the Tariff of 1789, which authorized the collection of duties on imports.

[16] Purchases include the Louisiana and Oregon territories; Florida, Alaska, and Washington, D.C.; funding the National Road and the Transcontinental Railroad; building many of the United States' lighthouses; and military academies.

[19] In the early 20th century, Congress's primary interest in immigration was protecting American workers and wages – the reason it had become a federal concern in the first place.

[20] After World War I, Congress attempted to stem the flow of immigrants, still mainly coming from Europe, by passing laws in 1921 and 1924 limiting the number of newcomers by assigning a quota to each nationality based upon its representation in previous U.S. census figures.

[24] On September 13, 2019, Director Troy Miller rang the closing bell at the New York Stock Exchange in honor of 230 years since the beginnings of the CBP.

CBP officers defend against terrorist intrusion by identifying high risk individuals who are attempting to enter into the United States; stop criminal activities – such as drug trafficking, child pornography (including on computers, cell phones, and other electronic media), weapons trafficking, and money laundering – by inspecting vehicles and trucks; and prevent the illegal entry of individuals, the smuggling of prohibited goods, and other customs and immigration violations.

After a few years of service, qualified Officers may serve on CBP's Special Response Team after passing a pre-test and an additional five weeks of paid training at the U.S. Border Patrol Tactical Unit (BORTAC) in El Paso, Texas.

They serve as expert and technical consultants in the areas of inspection, intelligence, analysis, examination and law enforcement activities related to the importation of agricultural and commercial commodities and conveyances at the various ports of entry.

Import specialists work alongside CBP officers, Homeland Security Investigations special agents and legal professionals in matters of international trade.

They determine which products may legally enter the country by enforcing laws protecting public health and safety, intellectual property rights and fair trade practices.

Import specialists have the authority to issue penalties and fines, to recommend seizure of prohibited or suspect cargo and to participate in negotiations and legal prosecution.

Responsibilities could include investigating foreign manufacturing facilities for violations involving child labor, product safety or other areas of concern to the country.

Agents detect and prevent the smuggling and unlawful entry of aliens into the United States, along with apprehending those people found to be in violation of immigration laws.

This specialized law enforcement capability allows AMO to make significant contributions to the efforts of the Department of Homeland Security, as well as to those of other federal, state, local, and tribal agencies.

To accomplish its mission, AMO employs over 1,200 federal agents at 70 locations, operating more than 260 aircraft of 26 different types, and approximately 300 maritime vessels.

Based on the survey, the primary concerns are about promotion and pay increase based on merit, dealing with poor performance, rewarding creativity and innovation, and the inability of leadership to generate high levels of motivation in the workforce, recognition for doing a good job, lack of satisfaction with various component policies and procedures and lack of information about what is going on with the organization and complaints from the traveling public.

[37][38] In June 2007, CBP commissioner W. Ralph Basham announced to employees that the agency would be conducting 125 different focus groups in 12 different cities around the country to better understand their concerns as expressed in the Human Capital Survey.

[46] National Public Radio's Morning Edition reported that CBP radiation-detection equipment at ports is better at detecting kitty litter than dangerous weapons, and that U.S. borders are so porous that congressional investigators carrying simulated nuclear materials have walked across unchallenged.

He says that DHS and CBP suffer from "seriously flawed decision-making", citing the "door only" policy, radio frequency identification technology, and lack of focus on exports which contain bombs.

[48] The agency's practice of performing internal document checks on buses and trains running entirely within U.S. territory has been called "coercive, unconstitutional, and tainted by racial profiling".

The court found that there were errors in the laboratory reports, that CBP destroyed the evidence, and the tests used by the chemist did not meet any Daubert standards.

[51] A 2018 report by the ACLU and University of Chicago Law School's International Human Rights Clinic alleged that there was pervasive physical, verbal, sexual and psychological abuse of immigrant minors by DHS and CBP officials over the period 2009–2014.

Border Patrol chief Carla Provost said that the "posts are completely inappropriate" and vowed to hold the employees responsible accountable.

[55] In July 2020, the Trump administration dispatched federal officers to Portland, Oregon, during protests in the city following the murder of George Floyd.

[56][57][58] US Customs and Border Protection was named in the resulting suit filed by the Oregon Department of Justice, which accused CBP and other federal agencies of violating protesters' civil rights.

Senator Ron Wyden addressed an official letter to the CBP commissioner, raising concern about "allowing indiscriminate rifling through Americans' private records" and asking that the searches be limited to criminal investigation suspects and known security risks.