Questions over mass deportations are testing Trump's respect for law

If you believe the story the way the White House tells it, it's a black-and-white tale of triumph over evil.

Hundreds of dangerous gangsters, intent on raping and murdering Americans, taken off the streets in one fell swoop.

Their deportation was depicted in a slick online video, featuring a dramatic action-movie score. Shackled captives were dragged off planes, their heads shaved by masked guards before they were caged.

The Trump administration says the men are all "heinous monsters" from Tren de Aragua, a violent Venezuelan gang known for drug-smuggling and sex-trafficking across Latin America.

"Rapists, murderers, kidnappers, sexual assaulters, predators who have no right to be in this country," spokeswoman Karoline Leavitt said.

They were flown to El Salvador last weekend and locked in its mega-prison, where inmates spend more than 23 hours a day in crowded, mattress-less cells.

El Salvador says they'll be held there for at least a year. The US says it's paying El Salvador $US6 million ($9.6 million) to take them.

It's not clear what will happen to them in a year's time, but the Salvadoran president calls the prison term "renewable".

And it's led to another extraordinary legal stoush between President Donald Trump and the courts.

But who was actually on the plane?

The 238 men were whisked away with little warning. And civil rights groups and immigration lawyers say it appears innocent men were swept up in the operation.

Some of their relatives only learnt where their loved ones were when they spotted them in the social media video.

"My heart broke in a million pieces," the wife of Mervin Yamarte, one of the deportees, told the Washington Post.

"Because my husband is not part of Tren de Aragua. And I couldn't believe they sent him there."

Yamarte, a 29-year-old soccer player, had been working at a restaurant in Texas. His family says he'd come to America to earn money to help his wife and four-year-old daughter back home, where he soon planned to return.

Yamarte's mother said her son phoned her last Saturday to say he and several friends had been detained. They signed deportation papers and agreed to return to Venezuela.

Their families were horrified to learn they were instead thrown into a Salvadoran prison famous for its horror conditions.

Multiple similar stories have surfaced in the week since the deportations took place.

'We don't want to make that kind of mistake'

It's not clear how the US determined the deportees were criminals. The US government has conceded in court that some have clean records in the US.

The White House said this week it was "confident in DHS (Department of Homeland Security) intelligence assessments on these gang affiliations and criminality". In court, the government's argued surveillance data and interviews were among the evidence considered.

But there are no specifics. Some of the men, via their lawyers or their families, say they were targeted over tattoos wrongly interpreted as gang-related.

On Friday, Trump was asked about concerns not all the deportees were gang members or criminals.

"Well, I was told that they went through a very strong vetting process, and that that will also be continuing in El Salvador," he said.

"And if there's anything like that, we would certainly want to find out. But this was a bad group, and they were in bad areas, and they were with a lot of other people that were absolutely killers, murderers, and people that were really bad with the worst records you've ever seen.

"But we will continue that process. Absolutely. We don't want to make that kind of mistake."

Questions over use of wartime law

The legal justification for many of the deportations rests on a 18th century law, which has previously only been used during wartime.

The Alien Enemies Act allows for the detention and deportation of non-citizens from "enemy" nations. Its most contentious application, and the last time it was invoked, was to put Japanese Americans in internment camps during World War II.

In invoking the law, Trump has essentially declared that Venezuela is an enemy country behind some kind of invasion threat, and that the gang is controlled by that country's government.

Many legal experts say the law appears to have been improperly used.

It also means the men have been imprisoned without any due process. No chance to argue their case in court or even agree to self-deport home.

As the operation was underway, a federal judge — sceptical about this use of the wartime law — ordered the government to hold off. It did not.

The government later argued the planes were already in the air when the judge's written order came out. His earlier verbal order, the White House argues, didn't really count.

"There's actually questions about whether a verbal order carries the same weight as a written order," the White House's Leavitt said earlier this week.

Legal showdown

Federal judge James Boasberg doesn't seem to think his verbal order was worth so little. He's been sparring with the government in the week since, as he examines whether it willingly defied him.

He's made repeated requests for information from the government, and expressed frustration with "woefully inadequate" and "disrespectful" responses provided so far.

Trump and his allies have meanwhile spent the week publicly laying into the judge.

One of Trump's social media attacks — an extraordinary call for the "troublemaker" judge's impeachment — clearly annoyed the Chief Justice of the Supreme Court, who responded with a rare rebuke.

But Trump ally Elon Musk has since reportedly made sizeable donations to Republicans who have pushed to impeach judges. His America First political fundraising group is offering $100 cash to voters in Wisconsin who sign a petition against "activist judges".

Trump's attacks on the judiciary before the election, as he personally fought criminal prosecution, was one thing.

But he's continued them from the White House, stress-testing the separation of powers that are vital to keep checks and balances on any president.

"The government's not being terribly cooperative at this point," Judge Boasberg said Friday.

"But I will get to the bottom of whether they violated my order, who ordered this and what the consequences will be."