Dear Ms. Matthews,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located the Subject Index to Correspondence and Case Files, 1903 - 3/31/1957 (Microfilm Publication T458) in the Records of the Immigration and Naturalization Service (Record Group 85) that serves as an index to part of the Subject and Policy Files, 1906 - 1957 in Record Group 85 that may include a record of the Board of Special Inquiry hearing. Since these records are not digitized, we were unable to determine if there is any information about Wilheim Bratkowski’s emigration to the United States or his deportation to France instead of Poland, his country of origin. For more information about these records and T458, please contact the National Archives at Washington DC - Textual Reference (RDT1) via email at firstname.lastname@example.org.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT1. We apologize for this inconvenience and appreciate your understanding and patience.
For information about him while in France, we suggest you contact the National Archives of France (Archives Nationales), 59 rue Guynemer, 93380 Pierrefitte-sur-Seine, France. The web site is http://www.archives-nationales.culture.gouv.fr/en/web/guest.
You may wish to review these websites: Poland Emigration and Immigration and Early Twentieth-Century Deportation and the Resistance - The Center for Migration Studies of New York (CMS) for more information.
We hope this is helpful. Best of luck with your family research!