The Ninth Circuit has determined that a District Court maintains the authority to naturalize an applicant, even if removal proceedings are pending.  According to the government, 8 U.S.C. § 1429 precluded a court from considering a naturalization application when the applicant had been placed in removal proceedings.  "Because the  USCIS did not issue final decisions on the Yiths’ naturalization applications within 120 days after their examinations, the district court had jurisdiction to adjudicate their naturalization applications under 8 U.S.C. § 1447(b) and correctly rejected the government’s argument that the commencement of removal proceedings stripped the district court of subject matter jurisdiction."  Moreover, § 1447(b) applies only to the Attorney General, and thus, the existence of an on-going removal proceeding does not strip the District Court of authority to adjudicate a naturalization application.  

The court distinguished the instant scenario from one in which the agency denies a naturalization application because removal proceedings are pending.  "Unlike § 1421(c), which applies when an agency denies an application, § 1447(b) applies when the government fails to make a determination within a 120-day period and gives the district court jurisdiction over the entire 'matter.'  Here, the USCIS did not deny the Yiths’ naturalization applications, and so the district court’s review is not limited to the reason for the agency’s denial, but extends to the entire matter (i.e., the application for naturalization) that was pending before the agency.”  "[W]e adopt the straightforward reading of the statute that the USCIS fails to make a determination under § 1447(b) when it fails to deny the applications before the statutory deadline."  

The Court also considered the language in § 1429 that the government may not consider an applicant’s naturalization application “if there is pending against the applicant a removal proceeding pursuant to a warrant of arrest issued under the provisions of this chapter or any other Act.”  The Yiths argued that § 1429 does not apply to them by its terms because their removal proceeding was not pursuant to a warrant of arrest. The government argued that the Court should defer to the DHS’s regulatory interpretation of “warrant,” which states that for the purposes of 8 U.S.C. § 1429, "a notice to appear issued under 8 CFR part 239 (including a charging document issued to commence proceedings under sections 236 or 242 of the Act prior to April 1, 1997) shall be regarded as a warrant of arrest.” 

The Court disagreed, finding that the meaning of “warrant of arrest” in § 1429 is unambiguous.  Specifically, a warrant of arrest is is a writ issued under § 1226 authorizing law enforcement personnel to arrest and detain an alien pending the results of removal proceedings.  This document is distinct from a Notice to Appear.  "Although the Yiths received a notice to appear, they were not subject to 'a warrant of arrest issued under the provisions' of Chapter 12 of the INA. Accordingly, their removal proceedings were not pursuant to such a warrant of arrest, and this portion of § 1429 was inapplicable to their case."  "By its terms, § 1429 precludes only the executive branch from considering an applicant’s naturalization application, and only when there is pending against the applicant a removal proceeding pursuant to a warrant of arrest."

The full text of Yith v. Nielsen can be found here: