A Honduran migrant couple and their five kids taking part in a caravan heading to the US, wait to cross the border from Ciudad Tecun Uman in Guatemala, to Ciudad Hidalgo, Mexico, on October 22, 2018. Orlando Sierra | AFP | Getty Images

Six Honduran migrants walking in a "caravan" to seek asylum at the U.S.-Mexico border filed a class-action lawsuit against President Donald Trump, Attorney General Jeff Sessions and other key figures, arguing the administration's immigration proposals are "shockingly unconstitutional." The civil suit, filed Thursday in U.S. District Court in Washington, D.C., claims Trump "continues to abuse the law, including constitutional rights, to deter Central Americans from exercising their lawful right to seek asylum in the United States." The migrants' attorney, John Shoreman, argues that some of Trump's policy proposals violate the due process clause of the Fifth Amendment, which holds that "no person shall ... be deprived of life, liberty, or property, without due process of law." Even undocumented immigrants have due process rights under U.S. law, though that can vary depending on the legal precedent being applied, PBS reported.

The six Honduran nationals and their children are asking the federal court to declare a number of Trump's recent policy proposals to be in violation of the supreme law of the land "to end this case and controversy." Homeland Security Secretary Kirstjen Nielsen, Immigration and Customs Enforcement, Customs and Border Patrol, and Citizenship and Immigration Services are also included as defendants in the suit. Ahead of the midterm elections, Trump has ratcheted up both his rhetoric and policy proposals on immigration issues, zeroing in on the caravans. The president has repeatedly described the groups as an "invasion," and on Wednesday said he might deploy up to 15,000 military personnel to the border to keep the migrants out. Shoreman said in a court filing that "the plaintiffs are seeking asylum, and Trump simply cannot stop them from legally doing so by using military, or anyone." The lawyer did not immediately respond to CNBC's request for an interview. Trump has also floated the possibility of an executive order to end the longstanding policy of birthright citizenship for people born to noncitizens within the U.S. — an action many legal experts say would violate the Constitution. On Thursday, the president said he planned to block arrivals from making asylum claims outside of designated ports of entry, in spite of current asylum law. "The fact that innocent children are involved matters none to President Trump," Shoreman said. The lawsuit arrives with less than a week before the midterms, even as the caravans remain weeks away from America's southern border.