One Tip For Naturalization Delays:
Before a naturalization applicant has had an interview, they can seek a remedy by filing a Mandamus/APA action. If 120 days have passed since a naturalization applicant has had an interview without a decision, the applicant can file a lawsuit under 8 USC § 1447(b) to address the delay.

One Tip For Naturalization Naturalization Denials:
Once USCIS denies a naturalization application, a lawsuit can be filed in federal district court under 8 USC § 1421(c) seeking a de novo review of the application. However, before seeking judicial review in federal district court, the applicant should first exhaust the administrative appeal process by submitting a Form N-336 as a number of courts have held that the N-336 stage is a statutory exhaustion requirement.