(CNN) The number of pending cases in US immigration courts hit a record high this year and the trend shows no sign of slowing down.

With more than 700,000 open cases as of May, judges face a heavy case load. To alleviate the burden, two retired federal judges have proposed a solution: bring jurists like them back to the bench.

"We certainly have the expertise. We've handled heavy dockets of cases and we're accustomed with having to get up to speed very quickly in various areas of the law," retired US District Court Judge Marilyn Hall Patel said.

Patel and retired Judge D. Lowell Jensen sent a letter with the recommendation earlier this month to Attorney General Jeff Sessions and James McHenry, director of the DOJ's Executive Office for Immigration Review. The Department of Justice did not respond to a request for comment on Thursday night.

"We are aware that at this time there are extraordinary burdens and backlogs faced every day by the country's immigration judges, particularly along the southern border. We believe retired federal judges are a valuable untapped resource who could be called into service to assist in handling the immigration caseload fairly and efficiently," the pair wrote in a letter dated July 12.

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