by A Martínez and Dorian Merina an hour ago

Ross D. Franklin AP
Young detainees being escorted to an area to make phone calls as hundreds of mostly Central American immigrant children are being processed and held at the U.S. Customs and Border Protection Nogales Placement Center in Nogales, Ariz

For the first time in six years, the number of completed cases at the nation's busy immigration courts has risen, perhaps turning a corner on the long-standing backlog of cases.

That's according to federal data obtained by Syracuse University's Transactional Records Access Clearinghouse, or TRAC, that finds that judges completed 198,105 cases in 2015, up 7.3 percent from the previous year.

The data also shows a continued shift in where migrants are coming from with Mexico dropping by nearly 10 percent while Central American countries – such as Guatemala, Honduras and El Salvador – taking a bigger share of the court's docket. Mexico still represents the largest number of cases overall.

Still, pending cases exceed 460,000 nationwide, which presents a big challenge for overwhelmed courts, said Emily Ryo law professor at the University of Southern California's Gould School of Law.

"There's been an enormous backlog of immigration cases that has been clogging up the system," said Ryo. That makes things hard for an immigration system that has long had fewer resources than federal district courts.

"Immigration judges handle 1,400 to 1,500 cases per year on average, with only about one law clerk spread out across four immigration judges," said Ryo.

That's put a big strain on judges and staff, who are charged with hearing often complex cases and determining who should be removed and who can stay.

"Since the summer of 2014, the immigration courts have received tens of thousands of cases involving unaccompanied children and families who crossed the southwest border," said LaFondra Lynch, regional public information officer at the Executive Office for Immigration Review, in a statement.

Many of those cases were put in a priority docket to speed up the process for juveniles.

"Most priority cases completed to date have been removal orders, and many of those removal orders have been issued in absentia," she said, using the term to describe when a person fails to show up in court before a judge. But, she added, the priority for the agency continues to be cases in which the person has been "convicted of serious crimes."

Recent numbers from US Customs and Border Protection also show a rise in apprehensions along the southern border, indicating that another surge may be ahead.

"The immigration issue will really play an important and prominent role in the upcoming election year," said Ryo, the law professor at USC.

The Executive Office of Immigration Review also called the past several years "a tremendous challenge" for the agency and sent Take Two this statement:

"The 2014 border surge put unprecedented pressures on EOIR, and our agency responded by updating its practices and policies, which streamlined and strengthened the immigration court system. EOIR is hiring immigration judges to increase the size of the immigration judge corps, thereby augmenting adjudicatory capacity and working to reduce the case backlog and wait times for those in proceedings."

Last month the EOIR announced the hiring of six assistant chief immigration judges, saying that the new judges would take on management roles and hear cases directly.