LOS ANGELES (AFP) - United States immigration judges say they are under increasing pressure from President Donald Trump's administration to speed up immigrant deportations - or risk removal if they delay.

This pressure was highlighted in the case of Judge Steven Morley who was informed that a case he was handling was reassigned to another court so it could be closed and deportation procedures could begin.

The National Association of Immigration Judges (NAIJ) filed a grievance on Aug 8 with the US Department of Justice for what it considers a violation of courtroom authority.

The judge "should be left alone and protected in his ability to handle the case from the beginning", said NAIJ president Ashley Tabaddor, who told AFP she felt she had "a target on my head" for speaking out.

In the US, immigration courts are part of the executive - not the judicial - branch of government. Judges are appointed by the US attorney-general, who is the head of the Department of Justice.

Since the judges are appointed, the attorney-general can also fire them.

Mr Trump came to office spouting anti-immigrant rhetoric, especially against Mexicans, calling them drug dealers, criminals and "rapists".

Attorney-General Jeff Sessions, an early Trump supporter and immigration hardliner, announced this year that he would evaluate these judges based on the number of cases they close - in an overloaded system with hundreds of thousands of open cases.

The NAIJ also filed a complaint over this measure.

"There is anxiety and concern among the judges," Ms Tabaddor told AFP. The judges "feel tremendous pressure to try to do more work faster".

Immigration cases "are not like some product that's being manufactured where you can do everyone in a certain amount of time", said NAIJ president emeritus Dana Leigh Marks.

Some cases involve people seeking to immigrate because their lives are threatened in their home countries.

"We are deeply aware of the fact that the stakes in these cases are incredibly high," she told AFP, adding that the current system amounts to hearing "death penalty cases in a traffic court setting because the volume is so intense". And those cases take time.

A spokesman for the Justice Department's Executive Office for Immigration Review (EOIR) said action was taken in Judge Morley's case because of "potential violations of processes and practices governed by federal law and EOIR policy", but gave no specifics.

"In any situation where a concern is raised about an immigration judge's conduct, regardless of whether that concern is raised by a representative, third-party group, or following an internal review, EOIR's OCIJ (Office of the Chief Immigration Judge) investigates the issue thoroughly and will address it appropriately as the facts warrant. We look forward to fully vindicating the issues surrounding this matter."

'WORST NIGHTMARE'

In Philadelphia, Judge Morley was handling an immigration request from Guatemalan Reynaldo Castro-Tum, who crossed the border into the US unaccompanied in 2014 when he was 17 years old.

Mr Castro-Tum was handed over to his brother-in-law living in the US. Officials used that address to contact him.

The court sent Mr Castro-Tum five citations - but the Guatemalan never showed up.

Judge Morley gave the case an "administrative closure", meaning a pause to make sure that Mr Castro-Tum was actually receiving the court summons.

The letters for Mr Castro-Tum were going to a trailer park community, according to CNN. But it was not known if the family had moved.

Mr Sessions - who in this case can operate unilaterally - overturned Judge Morley's decision, arguing that immigration judges do not have the authority to close cases.

He ordered a new citation, meaning that if Mr Castro-Tum did not show up for a May 31 hearing, he would be deported.

The hearing came, and Mr Castro-Tum was again absent.

Judge Morley agreed to a request by attorney Matthew Archambeault for time to try to find the young man - but soon after received an e-mail from Assistant Chief Immigration Judge Jack Weil informing him that the case had been reassigned because Judge Morley "had been expected to make a decision" on May 31.

A judge was sent from Washington to close the case and order Mr Castro-Tum's deportation, even though it's unclear if the Guatemalan is still in the US.

"It's kind of our worst nightmare come true that the department seems to be unhappy with how he's handling a case," Ms Marks said. So they take the case away and hand it to a judge "that they feel is going to be more amenable to their perspective", she said.

Ms Marks said all administrations have exerted pressure of some kind on immigration judges, including Mr Trump's predecessor Barack Obama, but "no other time than now have they become as pronounced as they are".

Under Mr Trump, "they have crossed all the lines and done so with gusto", she said.