Two immigrants and three attorneys said they are seeking class-action status for thousands of people waiting more than 30 business days to get the documents from the U.S. Department of Homeland Security.
The plaintiffs, who are represented by the American Immigration Council and other immigrant rights advocates, sued in federal court in San Francisco.
Immigrants need the files to review details in their own immigration histories to defend themselves against deportation and apply for asylum, green cards and citizenship, advocates said.
The records, known as immigrants' A-files, contain information about how they came into the country and any immigration benefit applications they have submitted.
The delay "causes unnecessary emotional and financial hardship for individuals left in legal limbo while they wait to obtain the records that hold the key to assessing their immigration options in the United States," the lawsuit said.
A spokesperson for U.S. Citizenship and Immigration Services didn't immediately comment.
The U.S. immigration system is facing massive backlogs in naturalization applications, asylum filings and the immigration courts. Advocates have decried lengthy waits for citizenship interviews and asylum hearings, and with the lawsuit, they are adding the ability to obtain immigration documents to the list.
The numbers of pending asylum applications and immigration court cases have grown since the Trump administration's immigration crackdown and a rise in children and families arriving on the southwest border, many from Central America.
About 41,000 Freedom of Information Act requests were pending at U.S. Citizenship and Immigration Services in the 2018 fiscal year, the lawsuit said.
Claudia Valenzuela, FOIA staff attorney at the American Immigration Council, said she didn't know how many are from people seeking their own A-files but believes there are thousands.
The average processing time for A-file requests ranges from 55 to 90 days, according to the Citizenship and Immigration Services website.
Cheryl David, an immigration attorney in New York and a plaintiff in the lawsuit, said wait times for A-files aren't new. She said it regularly takes her about eight months to get the documents and they are critical to prepare a case, especially when immigrants have lived in the U.S. for a long time and may have filed applications previously on their own or with other lawyers.
"You don't want to go into an immigration interview blind as to what your client has applied for before or has submitted to immigration if they don't remember," she said.
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