David B. Rivkin Jr. and Lee A. Casey [“Obama’s illegal move on immigration,” op-ed, Sept. 3] blithely assert the illegality of a recent Obama administration announcement, which encouraged the closure of lower-priority cases so that the overburdened immigration court system could more adeptly handle the cases of immigrants who have dangerous criminal convictions or pose security risks. They assert that only Congress sets immigration policy.

Perhaps these gentlemen could join my law students in studying the cases establishing the federal power to regulate immigration — the late-19th-century cases of Chae Chan Ping v. U.S., Ekiu v. U.S. and Fong Yue Ting v. U.S., which explicitly defer to the “political departments,” both executive and congressional.

President Obama is acting well within the powers conferred by Congress. Beyond the unquestionable constitutionality, it is simply good policy to let the executive branch clear the debilitating court backlog to allow its enforcement work to be smarter and more effective.

Elizabeth Keyes, Washington

The writer teaches immigration law at American University’s Washington College of Law.

●The op-ed by David B. Rivkin Jr. and Lee A. Casey rested on a false premise: that the Obama administration has decided to deport only those who have committed crimes in the United States.

An Aug. 18 letter by Homeland Security Secretary Janet Napolitano to Sen. Richard Durbin (D-Ill.) repeated the administration’s position that it “makes no sense to expend our enforcement resources on low-priority cases,” such as those of young people “who were brought to this country as young children and know no other home.” 

But that does not mean, as Mr. Rivkin and Mr. Casey argued, that “no enforcement resources will be expended on those who do not pose a threat to public safety.” They conceded that President Obama “has not declared his intent to dispense with immigration law.”

In fact, by every enforcement strategy and metric — interdictions, visa controls, border enforcement, workplace audits, fines and debarments, and criminal prosecutions — the administration has aggressively enforced the law. If trends continue, it will remove roughly 1.5 million noncitizens over four years, compared with 2 million removals during the eight years of George W. Bush’s presidency.

Donald Kerwin, New York

The writer is executive director of the Center for Migration Studies.