Adds new section 1123 to title 18 creating the offense 'Killing of law enforcement officers', defining multiple terms (e.g., federal law enforcement officer, federally funded public safety officer, judicial officer, law enforcement officer) and establishing penalties including minimum imprisonment terms and, if death results, possible death penalty.

Adds new section 120 to title 18 creating the offense 'Assaults of law enforcement officers', defining 'federally funded State or local law enforcement officer', specifying offenses, penalties with graduated imprisonment ranges, a certification requirement for federal prosecution by the Attorney General (or designee), and a statute of limitations.

Adds new section 1075 to title 18 creating the offense 'Flight to avoid prosecution for killing law enforcement officials', prohibiting interstate or foreign travel with intent to avoid prosecution or custody related to killings of Federal judges, Federal law enforcement officers, or federally funded public safety officers, and prescribing penalties.

Inserts new section 3054 into chapter 203 of title 18 authorizing sworn officers, agents, or employees of the United States, a State, or political subdivisions who are authorized to enforce or supervise enforcement of law (or supervise/secure safety of incarcerated inmates) to carry firearms if authorized by law, and explicitly including possession incident to depositing a firearm within a secure firearms storage area for use by authorized persons within buildings or structures classified as Federal facilities or Federal court facilities and their grounds (as defined in section 930).

Amends 18 U.S.C. 930(d) to add an exception permitting possession of a firearm or ammunition in a Facility Security Level I or II civilian public access facility by a qualified law enforcement officer (as defined in 926B(c)) or a qualified retired law enforcement officer (as defined in 926C(c)), and adjusts punctuation in existing paragraphs (2) and (3) to integrate the new paragraph; amends 18 U.S.C. 930(g) to add definitions for 'Facility Security Level' and 'civilian public access facility'.

Replaces the existing ‘‘except that in any action…’’ clause in 42 U.S.C. 1983 with new limiting provisions: (1) restates the limitation on injunctive relief against judicial officers unless a declaratory decree was violated or declaratory relief was unavailable; and (2) adds a new limitation barring awards of damages (other than necessary out‑of‑pocket expenditures and other monetary loss) where the deprivation arose in the course of, as a result of, or related to conduct by the injured party that more likely than not constituted a felony or a crime of violence (as defined in 18 U.S.C. 16).

Replaces the existing ‘‘except that…’’ clause in 42 U.S.C. 1988(b) regarding attorney’s fees with two clauses: (1) restates that judicial officers are not liable for costs including attorneys’ fees unless the action was clearly in excess of their jurisdiction; and (2) adds that in actions where the deprivation was incurred in the course of, as a result of, or related to conduct by the injured party that more likely than not constituted a felony or crime of violence, the court may not allow that party to recover attorney’s fees.

Adds a new subsection (j) to 28 U.S.C. 2254 that limits federal habeas relief for persons in custody pursuant to state-court judgments for crimes involving the killing of a public safety officer (as defined at 34 U.S.C. 10284) or judge while engaged in official duties (or on account of official duties/status); makes such applications subject to the time limitations and other requirements of 28 U.S.C. §§ 2263, 2264, and 2266; bars courts from considering sentencing claims adjudicated in state court; and provides that 28 U.S.C. §§ 2251, 2262, and 2101 are the exclusive sources of authority for federal courts to stay a state death sentence in such cases.

Strikes the phrase 'the subject of a petition' and all that follows in 28 U.S.C. 2244(b)(3)(E) and inserts replacement text (replacement text not provided in the excerpt).

Inserts a new paragraph (17) into 18 U.S.C. 3592(c) establishing as an aggravating factor for federal death-penalty cases that the defendant killed or attempted to kill a person authorized by law to (A) engage in or supervise prevention, detention, or investigation of criminal violations; (B) arrest, prosecute, or adjudicate an individual for criminal violations; or (C) be a firefighter or other first responder.