I-854, Inter-Agency Alien Witness and Informant Record
December 10, 2021
Form I854A will be used by Law enforcement to request a noncitizen witness or informant to receive classification as an S nonimmigrant. Form I-854B will be used by law enforcement agencies to request a noncitizen in S nonimmigrant status to be permitted to apply for an adjustment of status to a lawful permanent resident under section 245(j) of the Immigration and Nationality Act.
Specific content can be found here:
https://www.politico.com/news/2021/12/04/immigration-system-labor-squeeze-523744