By IAN URBINA and CATHERINE RENTZ

DO immigrants who are incarcerated while their legal status is resolved deserve a lawyer?

On a given day, roughly 34,000 immigrants are held in a patchwork of local jails and prisons, awaiting court hearings that determine whether they have the legal right to remain in the United States or will be deported. The recent revelation that roughly 300 immigration detainees are being held in solitary confinement — conditions that the United Nations special rapporteur on torture and others have said can constitute torture — highlights how punitive, costly and legally fraught American immigration policy has become.

Fifty years ago, the landmark case Gideon v. Wainwright required state courts to provide counsel in criminal cases for defendants who could not afford lawyers. But people who are detained do not typically have lawyers because immigration law, unlike criminal law, does not provide a right to counsel. Immigrant detainees are allowed to hire lawyers, but more often than not, they cannot afford counsel or are shuffled through the system before they have a chance to find help.

Among the detainees not guaranteed representation are children, the mentally disabled, victims of sex trafficking, refugees, torture survivors and legal permanent residents. Free representation tends to be provided by lawyers at nonprofit advocacy groups that are ill equipped to keep up with demand.

The American immigration system is already wildly expensive, and providing lawyers for immigrants would make it even more expensive. In 2012, the Obama administration’s overall budget for immigration enforcement was $18 billion, significantly more than was spent by all other major federal law enforcement agencies combined, including the Federal Bureau of Investigation, the Secret Service and the Bureau of Alcohol, Tobacco, Firearms and Explosives, according to a report by the Migration Policy Institute, a nonpartisan research group in Washington.

Advocates of tighter controls on immigration say that guaranteeing detainees counsel would make matters only worse. With guaranteed representation, they argue, more immigrants would be allowed to stay. Studies have shown that having a lawyer during removal proceedings vastly improves an immigrant’s ability to defend against deportation. Without counsel, only 3 percent prevail in their asylum cases compared with 18 percent who have legal counsel.

Jon Freere, a legal policy analyst for the Center for Immigration Studies, a research organization based in Washington that advocates for reduced immigration, pointed out that American citizens routinely deal with important civil matters like child custody, foreclosures or evictions without the benefit of guaranteed legal representation.

“Why should illegal aliens be guaranteed greater protections than citizens?” he asked.

Throwing more immigration lawyers into the mix, he said, would probably slow the process only further, especially considering that immigration lawyers are always looking to expand the scope of asylum.

Other immigration opponents add that harsh detention conditions encourage immigrants to more quickly sign papers, agreeing to leave rather than adjudicate the matter. Switch to ankle bracelets and provide more detainees with lawyers, they argue, and immigrants will linger in the hands of Immigration and Customs Enforcement that much longer — and at considerable added taxpayer cost.

But immigrant advocates, civil rights lawyers and some immigration judges argue that providing guaranteed representation would actually help lower costs, lessen backlogs in the legal system and prevent miscarriages of justice, protecting people who have a right to stay in the country against deportation. The National Association of Immigration Judges wants to see more legal help for immigrants, arguing that representation would speed processing times because properly counseled immigrants are less likely to pursue claims that have no legal basis or to appeal in cases with little chance of success.

Paul Grussendorf, an immigration judge in Philadelphia from 1997 to 2001 and then in San Francisco until 2004, said he saw many immigrants pass before his bench, and although dozens were qualified to stay in the country, they were ultimately deported because they lacked legal representation.

Dozens of detainees who could have qualified to stay gave up after months in detention, he said, because they had no prospects of ever finding counsel to help them. He cited studies indicating that I.C.E. currently pays roughly $2 billion per year just to detain immigrants and that 80 percent of that cost could be saved by releasing immigrants but tracking them using ankle bracelets.

“The savings here could easily be used to offset the price of providing counsel for most immigrants being processed by I.C.E.,” Mr. Grussendorf said.

But Jan C. Ting, a law professor at Temple University and an assistant commissioner at the Immigration and Naturalization Service from 1990 to 1993, said that shifting to alternative means of custody like ankle bracelets risked slowing the process and raising costs because it could increase the instances when immigrants failed to show up at their hearings.

“Only those who have worked on the government side have any appreciation of how difficult and expensive it is to try to enforce our immigration laws,” he added.

If Congress does not resolve questions about legal representation, civil rights advocates say they may challenge the status quo in the courts.

In what he described as a “first shot across the bow,” Anthony D. Romero, the executive director of the American Civil Liberties Union, said that his organization filed a federal class-action lawsuit in 2010 aimed at testing the constitutionality of immigrants’ right to counsel.

The lawsuit, filed in California, was on behalf of immigrants with severe mental disabilities who were never provided lawyers. The lead plaintiff in the case, José Antonio Franco González, who has an I.Q. below 55, was wrongfully held by I.C.E. for five years, which the A.C.L.U. argues could have been prevented if he had had a court-provided lawyer.

“If the government is going to deprive an individual of his liberty through a legal process,” Mr. Romero said, “the government should provide a lawyer to those who cannot afford one.”

Ian Urbina is an investigative reporter for The New York Times. Catherine Rentz is an independent journalist based at the Investigative Reporting Workshop at American University.