In 2002 Edmer Rogelio Cabrera-Alvarez, an immigrant from Mexico, was arrested for driving under the influence. For ten years he had lived continuously in the United States and worked steadily (mainly in agriculture). He had set up a household with Santa Morales; they had two children, both U.S. citizens. When his arrest brought Cabrera-Alvarez to the attention of the state, an immigration judge ordered him deported for having entered the United States illegally in 1992.

Cabrera-Alvarez contested the deportation order, contending that his case should be governed by the United Nations Convention on the Rights of the Child, which states: “In all actions concerning children . . . undertaken by . . . courts of law, administrative authorities or legislative bodies, the best interests of the child shall be a primary consideration.” The outcome presumably best for the Cabrera-Alvarez children (aged eight and ten when the appeal was heard in 2005) would have been to continue living together as a family in the United States. Cabrera-Alvarez argued that if he were deported, the children would suffer financial hardship and severe emotional distress.

In denying the appeal, the U.S. Court of Appeals for the 9th Circuit Court contended that U.S. immigration law allows cancellation of removal only where it would cause “exceptional and extremely unusual hardship” (emphasis added) to the petitioner’s citizen or lawful permanent-resident family members. The standard is almost impossible to meet—it requires that children’s lives be endangered by violence or extreme poverty in the parent’s home country.

Setting the bar so high, the law allows for profound harm to citizen children. Cabrera-Alvarez and Morales faced two choices: separating Mr. Cabrera-Alvarez from his children, or moving as a family to Mexico, a country the children had never visited. The first option violates the childrens’ right to a parent-child relationship; the other rides roughshod over the citizen child’s right to reside in the United States. The child citizen is not herself technically “deported,” but in preserving family unity she endures “constructive deportation.”

By permitting citizens and permanent residents to petition to have a spouse (although not a spouse who is already illegally in the country) or their children enter as their “derivatives,” U.S. immigration law recognizes that living with one’s family is an important human interest. But there is a glaring asymmetry in its respect for family relationships: citizen children cannot assert their right to family unity either to prevent the deportation of a parent, or to sponsor a parent for legal immigration status, despite the fact that they have as strong an interest in preserving the parent-child relationship as do their parents.

This is unjust and unwise. Think what it means to a child, born and raised in the United States, to live in a household in which the threat of deportation of a parent is ever-present. Even as she develops what Joseph Carens calls the markers of “social citizenship,” her family lives in a state of constant insecurity. The child is eligible for social benefits, but the parents may be loath to apply for them. Any action that might bring a parent to the attention of the state is to be avoided. The parent cannot take the child to visit her grandparents and relatives abroad, since the parent cannot leave and reenter the United States. Exposure and deportation may be relatively infrequent, but that does not lessen the harm of the persistent and debilitating threat under which every member of the family lives, knowing that their family ties can be arbitrarily disrupted—indeed, destroyed—or, alternatively, be preserved only by leaving the sole country and way of life the children have ever known.

Carens gestures at the right to a family life, but focus on length of stay neglects the urgency of the child’s claim to family unity and overlooks helpful models that could guide policy. International human rights agreements and the laws of some other countries recognize the right to family life to a far greater extent than does U.S. law. Article 8 of the European Convention on Human Rights, for example, guarantees “respect for [one’s] private and family life,” and as a result the European Court for Human Rights has held that any deportation must be tested against the right to family unity. Article 9 of the United Nations Convention on the Rights of the Child (which, among UN member states, only the United States and Somalia have failed to ratify), declares that states “shall ensure that a child shall not be separated from his or her parents against their will, except when . . . such separation is necessary for the best interests of the child.” Many European countries and Canada have rejected attempts to deport irregular migrants, even those convicted of crimes, because of the overriding importance of mainting family unity in the state that the family calls home.

Under current U.S. law, as Jacqueline Bhabha of the Harvard Law School has argued, a “child’s interest in family unity is pitted against the state’s interest in enforcing immigration control,” and the child loses. While citizen children have a right to permanent residence, the law fails to recognize the most important condition necessary to that residence: the continued presence of parent-caregivers.

Family unity and maintenance of the parent-child relationship are not simply humanitarian principles—they are fundamental human rights. It is high time American policy-makers recognized the profound and inexcusable suffering that U.S. laws impose upon children. The rights of children, and of family relationships, must be granted the place in immigration law that they deserve.