Maria Garcia-Aguilar was arrested during a raid by Immigration and Customs Enforcement (ICE) on her workplace. She was handcuffed before she was asked any questions, and it was only after being transported to a military base that she was questioned by ICE officers about her identity and nationality. In the meantime, the Mexican consulate was alerted that Garcia-Aguilar had not returned home from work to pick up her young child, and consular officials faxed a request to ICE to release her. Along with the request, the consulate faxed Garcia-Aguilar's birth certificate.
In court, Garcia-Aguilar argued that her arrest, detention, and interrogation violated her constitutional rights (insomuch as she was arrested before ICE had any reason to believe she was in the country unlawfully), and asked that all evidence of her foreign birth, such as statements she made during the interrogation, be suppressed. She also asked that the birth certificate be suppressed, on the ground that but-for her unlawful arrest, the consulate would never have provided the birth certificate to ICE. The Immigration Judge denied her motion to suppress and the Board of Immigration Appeals affirmed.
The First Circuit agreed, finding that the connection between the raid and the voluntary submission of the birth certificate by the consulate was too attenuated. Even assuming the workplace raid was an egregious violation of the Constitution, the birth certificate was not tainted by the unlawfulness of the raid and could serve as evidence of Garcia-Aguilar's foreign birth.
The full text of Garcia-Aguilar v. Lynch can be found here: http://media.ca1.uscourts.gov/pdf.opinions/14-1185P-01A.pdf