Washington (CNN) President Donald Trump in recent days has fumed about the immigration courts that handle cases of people seeking entry into the US.

But Trump's fixation on the courts and the judges who staff them flies in the face of what his attorney general has been trying to do to reshape the courts to align with the President's vision, including hiring more immigration judges and restricting asylum laws.

The President tweeted that those stopped at the border should be simply told they can't enter, rather than going through the system.

"When somebody comes in, we must immediately, with no judges or court cases, bring them back from where they came," Trump tweeted on Saturday.

Press secretary Sarah Sanders told reporters Monday that "virtually all Americans" agree that drawn-out court proceedings don't make sense for migrants who enter the country illegally. Trump, she said, "would certainly like to see more expedited removal."

"Just because you don't see a judge doesn't mean you aren't receiving due process," she said.

The immigration courts decide whether immigrants have a legal right to stay in the US or should be deported -- and those cases include people arriving at the border as well people from the interior of the US, who may or may not have had legal status at some point.

But Trump's suggestion has several problems, including the fact that there are fewer than 350 immigration judges nationwide and the Justice Department has budgeted for only 100 more.

In addition, the suggestion that the immigration courts could be done away with altogether would likely fly in the face of the Constitution and a host of domestic and international laws that bestow rights on everyone in the US and crossing the border, regardless of whether they are citizens.

And at least some of the immigrants at the border do, in fact, have a right under US and international law to be allowed into the United States, even if they enter illegally.

Trump's administration has been fixated on the immigration courts, which suffer a sizable backlog that slows down cases, but not in the way the President is suggesting.

Unlike other federal courts, the immigration courts are entirely under the purview of the Justice Department and Attorney General Jeff Sessions. Among the moves Sessions has made has been to set performance quotas for judges, encouraging them to move cases along faster.

"To end the lawlessness and move to the virtuous cycle, we have to be very productive. Volume is critical," Sessions said at an annual training meeting for the nation's immigration judges earlier this month. "Let's be clear: We have a goal, and the goal -- and that goal is to end the lawlessness that now exists in our immigration system."

The backlog

One of the reasons there is bipartisan agreement that the system needs more immigration judges is the ever-growing backlog of cases, which was at nearly 700,000 as of March 31, according to the Justice Department.

Because of the increasing number of cases before the courts, the length of time immigrants wait for their cases to be heard is growing -- and it can take years to finish a case.

That has become an issue because it allows those immigrants in many cases to live and work in the United States while they wait. The Trump administration argues the backlog is because of fraudulent claims gumming up the system -- though it has presented no evidence that fraudulent cases are more than a minuscule fraction of the total.

According to Justice statistics, roughly 22% of asylum cases, for example, were granted this year as of mid-April. But not all the rest were denials -- roughly 42% were denied in the same time frame.

Judge hiring, efficiency

But there have been concerns raised about how Sessions is hiring judges and measures he has implemented to try to speed them up.

Because immigration judges technically work for Sessions and the Justice Department as nonpolitical federal employees, he ultimately appoints them to their positions. A handful of House Democrats have accused him of illegally screening applicants for perceived political ideology. One candidate for the Board of Immigration Appeals who had her job offer rescinded has gone public with her case to CNN, rejecting the explanation the department gave for reversing an offer that had been made to her pending a background check.

Additionally, Sessions has implemented performance measures for judges that require them to complete 700 cases a year -- something the judges' union says is not realistic and could either jeopardize the impartial court process or give the appearance of bias, which would only slow things down further by generating numerous appeals.

"We need to show noncitizens who may or may not be able to stay what a fair and unbiased American court system will provide," said Judge Dana Leigh Marks, president emeritus of the National Association of Immigration Judges. "That means their day in court, in front of an independent and neutral decision maker."

Sessions' other moves

Sessions has also tested the limits of his powers over the immigration courts in other ways.

As attorney general, he is granted the unique authority to serve as a one-man Supreme Court over the immigration courts, meaning he can choose to reverse appellate court decisions and set interpretations of law that all judges must follow.

He has already used this authority to reverse asylum protections for domestic violence victims and other victims of crime, a policy decision that will largely affect migrants from Central America.

He has also made other moves with this authority, including allowing judges to reject asylum claims without a hearing, shifting the burden of proof onto the migrant -- who is not provided legal representation by the government -- and making it harder for judges to close cases at their discretion.

Sessions' moves will likely have an impact beyond the courts and could be implemented right away at the border by those deciding which asylum claims are credible enough to move forward.