Okay... CBP is officially out of control.
https://www.linkedin.com/pulse/software-engineer-detained-several-hours-us-customs-given-fairchild
It was Sunday, Feb. 26, and the 28-year-old software engineer had left his home in Lagos, Nigeria, to come to the United States for the first time. It was a work trip. For the last six months, Omin had been working for Andela, a startup that connects the top tech talent in Africa with employers in the U.S. Andela accepts less than 1% of applicants into its program and is backed by Facebooks Mark Zuckerberg and Priscilla Chan. For this particular role, Omin was helping NYC-based fintech startup First Access create a JavaScript application for emerging markets and had secured a short-term joint B1/B2 visa.
...
Your visa says you are a software engineer. Is that correct? the officer asked Omin in a tone the engineer described as accusatory. When Omin said it was right, the officer presented him with a piece of paper and a pen and told him to answer the following questions:
Write a function to check if a Binary Search Tree is balanced.
What is an abstract class, and why do you need it?
To Omin who now hadnt slept in more than 24 hours the questions seemed opaque and could have multiple answers. While he is a skilled software engineer with more than seven years of experience, Omin later tells me that the questions looked to him like someone with no technical background Googled something like, Questions to ask a software engineer.
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Omin tells me that the answers to the questions were technically correct, but he suspects the customs official interrogating him wasnt technically trained and couldnt understand his answers.
Aaaaaaaaaaaaaaaaaaaaaaaaaaand the CBP is denying that something that clearly happened absolutely didn't happen:
On 3/1, a U.S. Customs and Border Protection spokesperson responded to the 2/27 request for comment. He said the agency "does not administer written tests to verify a travelers purpose of travel, but would not comment on Omins case specifically. He added that foreigners trying to enter the country "bear the burden of proof to establish that they are clearly eligible" and "must overcome all grounds of inadmissibility."