Fixing Internal Response to Misconduct Act or the DHS FIRM Act (Sec. 2) This bill amends the Homeland Security Act of 2002 to direct the Chief Human Capital Officer of the Department of Homeland Security (DHS) to implement a DHS-wide policy related to discipline and adverse actions, which shall provide guidance: to the senior human resources official overseeing discipline and adverse actions for headquarters personnel and non-component entities and relevant component heads regarding informing the public about how to report employee misconduct; on how DHS employees should report employee misconduct; on the type, quantity, and frequency of data regarding discipline and adverse actions to be submitted by such official to such officer; on how to implement any such policy in a manner that promotes greater uniformity and transparency in the administration of such policy across DHS; and on prohibited personnel practices, employee rights, and related procedures and processes. Such officer shall review and approve any necessary development of or changes to tables of offenses and penalties for DHS components to comply with DHS policy. Component heads shall comply with DHS-wide policy regarding discipline and adverse actions for DHS's workforce, and such officer shall implement a process to oversee such compliance. Such officer: (1) may establish working groups to address employee misconduct within DHS, (2) shall conduct follow-up reviews of components regarding implementation of working group recommendations, and (3) may request the DHS Inspector General to investigate any concerns identified through the oversight process that components have not addressed. A working group shall seek to identify any trends in misconduct, review component processes for addressing misconduct, and develop possible alternate strategies to address such misconduct.