; (B) the State has requested that the Federal Government assume jurisdiction; (C) the verdict or sentence obtained pursuant to State charges left demonstratively unvindicated the Federal interest in protecting the public safety; or (D) a prosecution by the United States is in the public interest and necessary to secure substantial justice. (2) Rule of construction Nothing in this subsection shall be construed to limit the authority of Federal officers, or a Federal grand jury, to investigate possible violations of this section. (d) Guidelines All prosecutions conducted by the United States under this section shall be undertaken pursuant to guidelines issued by the Attorney General, or the designee of the Attorney General, to be included in the United States Attorneys’ Manual that shall establish neutral and objective criteria for determining whether a crime was committed because of the actual or perceived status of any person. (e) Statute of limitations (1) Offenses not resulting in death Except as provided in paragraph (2), no person shall be prosecuted, tried, or punished for any offense under this section unless the indictment for such offense is found, or the information for such offense is instituted, not later than 7 years after the date on which the offense was committed. (2) Offenses resulting in death An indictment or information alleging that an offense under this section resulted in death may be found or instituted at any time without limitation. (f) Definitions In this section: (1) Law enforcement officer The term law enforcement officer means an employee of a governmental or public agency who is authorized by law— (A) to engage in or supervise the prevention, detention, investigation, or the incarceration of any person for any criminal violation of law