Hiu Lui Ng’s family may never know if he had to die, but he undoubtedly did not have to spend his last months in agony.

Ng is a Chinese computer engineer who died earlier this month in U.S. custody, two days after his 34th birthday. His case, as told by court documents cited by The New York Times, lends support to the growing call for better treatment of immigration detainees.

It also is cause for another look at concerns about a federal detention facility in our own back yard, the subject of a recent report alleging abuses.

But first Ng’s story. He came to the U.S. legally at age 17. He graduated high school, worked his way through community technical college and Microsoft training courses, and won a computer services contract.

He also overstayed his tourist visa and an unsuccessful application for political asylum. But when immigration authorities ordered him to court in 2001, they sent the notice to a nonexistent address. Six years later, when Ng and his wife, an American citizen, showed up for his green card interview, enforcement agents were waiting to arrest him.

So began a year of being shuttled through jails and detention centers in New England states. In April, Ng started to complain of severe back pain. According to court papers, detention officials dismissed Ng’s complaints and even his requests for a wheelchair once he could not stand.

Finally, after a judge intervened July 31, Ng got the care he needed. Doctors found cancer in Ng’s liver, lungs and bones, and a fractured spine. He died five days later.

Such abject neglect is unacceptable more than a year after Homeland Security’s inspector general cited a lack of timely and responsive medical care (among other problems) at federal detention centers.

Ng’s case is not unique. A Washington Post investigation concluded that 30 of the 83 immigration detainee deaths between 2003 and 2008 may have been caused by the actions, or inaction, of medical staff – including one at the privately run Northwest Detention Center on Tacoma’s Tideflats.

Northwest immigration officials dismissed the Post’s report, but advocates complain that the circumstances behind the death have never been fully explained. Last month, Seattle University School of Law’s human-rights clinic, together with the immigrant-rights group OneAmerica, released a report alleging human rights violations – including inadequate medical care – at the 1,000-bed Tacoma center.

The report is based on interviews of 41 anonymous detainees, making verification difficult. But federal immigration officials’ immediate dismissal of it as a “work of fiction” is not reassuring. Well-documented cases like Ng’s have established legitimate doubt about medical care in the nation’s growing network of immigration jails.

Mandatory standards for care in immigration custody, such as Congress is now considering, are due. So is better oversight. The penalty for overstaying a tourist visa shouldn’t be an agonizing death.