Raul A. Reyes is an attorney and member of the USA Today board of contributors. Follow him on Twitter @RaulAReyes . The opinions expressed in this commentary are solely those of the author.

Following new guidelines set out by Department of Homeland Secretary Jeh Johnson, immigration officials have begun reviewing the cases of families who have been detained. And last week the Obama administration announced changes to how women and children will be processed in immigration detention: Some of them will now be able to go free on bond, if they can show that they have a credible case for asylum or other relief.

Certainly these reforms are welcome, but they do not go nearly far enough. Our immigration detention system is a national disgrace, and should be abolished. It is costly, wasteful and inhumane. Worst of all, it flies in the face of American values of justice.

To be clear, "immigration detention" is really a euphemism for the network of roughly 250 prisons and jails around the country that house detainees.

The U.S. government has the largest immigration detention system in the world, and that is nothing to be proud of. The underlying problem with immigration detention is that most detainees are only guilty of being in the U.S. without authorization, which is a civil offense, not a crime.

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Yet detainees are treated like criminals, held behind bars and barbed wire, often in remote locations. In fact, in at least one respect, immigration detainees are treated worse than criminals: Criminal defendants have the right to a speedy adjudication and to court-appointed legal counsel. Immigration detainees do not.

Detention punishes people in disproportionate relation to their alleged infractions, and contributes to the misconception that undocumented immigrants are criminals.

The purpose of immigration detention, according to a report by the U.S. Council of Catholic Bishops , "is to ensure that noncitizens in removal proceedings appear for their hearings and ... that their removal can be effected." So people are, in effect, being jailed because of a hypothetical risk of flight.

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Not only is that unfair, in practice it is wildly expensive. The 2014 budget request for detention was $1.84 billion, a funding level that works out to about $5 million a day. The American Civil Liberties Union estimates that keeping a person in detention costs $161 a day; family detention costs $298 a day.

These costs are especially wasteful given that private companies control about 62% of the immigrant detention beds used by Immigration and Customs Enforcement . That means taxpayer money is going into corporate pockets.

Meanwhile, there are alternatives to detention that are much cheaper. The estimated costs of using electronic ankle bracelets or in-person reporting programs run from 17 cents to $17 a day, says the ACLU. These methods have proved effective as well. In 2013, one pilot program testing such alternatives reported a 99% appearance rate at immigration court hearings among participants, and 79% compliance rate for removal orders.

Right now, ICE invests a tiny fraction of its huge budget in such alternative programs. These programs deserve to be expanded, just as our existing detention network should be gradually phased out.

Beyond this, our detention system comes with a far greater human cost. It separates families and traumatizes children. In detention, people who have come to this country to work are subjected to unacceptable conditions, including, in some instances, lack of medical facilities.

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Some detainees have alleged sexual assault and verbal and physical abuse. Though a February report by the Department of Homeland Security found no evidence of abuse at one Texas detention center, there have been similar allegations of abuse at other facilities. Consider that it is likely that many such instances go unreported because of language barriers and fear.

It is no wonder that a group of congressional Democrats, recently returned from a tour of family detention facilities, said they were disturbed by what they saw. Rep. Luis Gutierrez, D-Illinois, referred t o one family detention center as "a prison camp."

True, we cannot simply release everyone who is in detention. Actually, that would be against the law, because Congress in 2009 set a "bed mandate" which specifies that immigration facilities must fill 34,000 beds a night with detainees. Think about what that means.

As NPR's Ted Robbins noted , "Imagine your city council telling the police department how many people it had to keep in jail each night." The law is illogical, and overturning it would be a good start toward ending detention. And ending detention is not a radical notion. In May, the editorial board of The New York Times endorsed the idea, calling detention "the most indefensible" part of the "country's broken-down immigration machinery."

We should not be locking up immigrants in prisons. Economics, common sense, and decency demand that we end immigration detention.