The money is part of a $750-million aid package for Central America's so-called Northern Triangle — Honduras, El Salvador and Guatemala — allocated under an Obama administration initiative.
Tens of thousands of families from the region have moved up through Mexico and sought asylum in the United States in recent years. The White House has said the financial package is necessary to reduce the crime and poverty spurring the migrants.
For Honduras to receive its portion of about $55 million, however, it had to prove to U.S. officials that it was meeting several conditions, including improvements in human rights, law enforcement and justice. The other countries also had to meet those conditions.
Honduras' record on those issues is abysmal, according to domestic and international human rights organizations, diplomats, free-press activists and judicial experts.
One notable abuse is the still unresolved shooting death early this year of Honduras' most prominent environmentalist activist, Bertha Caceres, with state security personnel suspected of involvement. The Honduran government has resisted offers of help from outside investigators.
Early this month, another prominent Honduran lands-rights activist and an associate were assassinated, and Caceres' organization says it is receiving death threats. Amnesty International declared Honduras a perilous "no-go zone" for many activists.
The State Department certified on Sept. 30 that Honduras had taken "effective steps" in meeting human rights criteria, however.
Members of Congress, especially those who wrote the conditions that Honduras was required to fulfill, did not agree.
"Over the past 25 years, the United States has provided hundreds of millions of dollars in aid to Honduras, with little to show for it," Leahy said in a statement to The Times.
"The conditions in our law are intended to prevent a repeat of past failures, when official corruption and impunity were ignored or excused, and to hold the government accountable. Virtuous rhetoric and half-steps are not enough," he added.
State Department spokesman John Kirby defended the decision to approve aid to Honduras, but said the administration would not "turn a blind eye" to egregious abuse.
"We are deeply concerned about the continued problems in Honduras from crime, corruption and impunity … and we always review our programs as a result of it," Kirby said Friday.
"As we stand here today, we are comfortable in the certification that we made," he added.
During the 1980s and 1990s, Honduras served as a launch pad for U.S. forces in a war against the leftist Sandinista government in neighboring Nicaragua. The U.S. government also supported the right-wing government of El Salvador, which was fighting its own uprising led by leftist guerrillas.
The wars are officially over, but violence led by gangs and drug traffickers now stalks El Salvador, Guatemala and Honduras, where political repression and fights over land fuel the toxic mix.
The three countries have some of the world's highest homicide rates. (Nicaragua remained relatively immune to the gang violence and is not part of the Northern Triangle initiative.)
The violence, coupled with endemic poverty, helped propel tens of thousands of children and families to journey north to the U.S. border in mid-2014, overwhelming the Border Patrol and local authorities.
In an effort to stanch the flow, the White House announced the Alliance for Prosperity for the three Northern Triangle countries, put Vice President
One-fourth of the money was released automatically. Another quarter was dispersed when the countries met conditions involving migration that were drafted by House members most interested in stopping the migrant flow.
The final 50% was tied to 12 rights-related conditions drafted by Leahy, who is a ranking member of the Senate Judiciary Committee.
Aware that his country's reputation has suffered, Honduran President Juan Orlando Hernandez recently appointed a "special envoy" to Washington "to foster greater dialogue and cooperation."
The envoy, former Foreign Minister Arturo Corrales, said in an interview that his government is making progress in meeting the U.S. conditions for aid.
Corrales noted that Honduras has accepted Honduran deportees from the United States even though they are returning to a country that suffers from widespread violence.
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5:45 p.m.: This article has been updated to reflect Sen. Leahy's remark that he could not support release of the funding for Honduras.