To seek the death-penalty, well, let's check the law:
18 USC § 242 - Deprivation of rights under color of lawOk, so the underlined is the conditions which constitute applicable here. Definitely applicable. The italicized is a 10-year max sentence, and much easier to activate: simply resist arrest for violating the weapons-ban and you'll incur some nice injury (or death) -- unfortunately this is unlikely to be able to go "up-the-tree" and hit the lawmakers. To seek the death penalty for these lawmakers we need to look at the bold portion.
Whoever, under color of any law, statute, ordinance, regulation, or custom, willfully subjects any person in any State, Territory, Commonwealth, Possession, or District to the deprivation of any rights, privileges, or immunities secured or protected by the Constitution or laws of the United States, or to different punishments, pains, or penalties, on account of such person being an alien, or by reason of his color, or race, than are prescribed for the punishment of citizens, shall be fined under this title or imprisoned not more than one year, or both; and if bodily injury results from the acts committed in violation of this section or if such acts include the use, attempted use, or threatened use of a dangerous weapon, explosives, or fire, shall be fined under this title or imprisoned not more than ten years, or both; and if death results from the acts committed in violation of this section or if such acts include kidnapping or an attempt to kidnap, aggravated sexual abuse, or an attempt to commit aggravated sexual abuse, or an attempt to kill, shall be fined under this title, or imprisoned for any term of years or for life, or both, or may be sentenced to death.
The problem we have here is that the language of the prohibition isn't exactly laying out the plan of kidnapping [or attempt thereof] in plain terms. So we have to look at the US Code definition of kidnapping:
(a) Whoever unlawfully seizes, confines, inveigles, decoys, kidnaps, abducts, or carries away and holds for ransom or reward or otherwise any person, except in the case of a minor by the parent thereof, when—We could argue that, as all commerce [and non-commerce] has been deemed "interstate commerce" for the sake of federal control (see Wickard v. Filburn & Gonzalas v. Raich [IIRC]), this means that the very act of the State paying the salaries of these representatives (and enforcement) qualifies as commerce -- The other thing, is if they use the USPS [for any reason] WRT the implementation of this law, makes any arrest attempts based thereof into kidnapping.
(1) the person is willfully transported in interstate or foreign commerce, regardless of whether the person was alive when transported across a State boundary, or the offender travels in interstate or foreign commerce or uses the mail or any means, facility, or instrumentality of interstate or foreign commerce in committing or in furtherance of the commission of the offense;
There is also the "death results from" or "attempt to kill" as well, this wold require proving that the proposed law is, in fact, an attempt to kill people. This sounds very much like "conspiracy theory" and therefore is going to be highly subjective on the part of the jury. -- Ideally it would be presented to the Grand Jury, pushing for them to issue a presentment. (Sadly, I haven't found a way to contact a grand jury.)
Next, let's look at this other law:
18 USC § 241 - Conspiracy against rightsNow this law would be much more conducive to catching a conspiracy... for the obvious reason. The mere proposing of this law could be violation of this law; again the proposal-to-dead-people line needs to be drawn. I believe that line exists; however, legally proving that is a bit of a challenge. One that I'm not sure I could do in court.
If two or more persons conspire to injure, oppress, threaten, or intimidate any person in any State, Territory, Commonwealth, Possession, or District in the free exercise or enjoyment of any right or privilege secured to him by the Constitution or laws of the United States, or because of his having so exercised the same; or
If two or more persons go in disguise on the highway, or on the premises of another, with intent to prevent or hinder his free exercise or enjoyment of any right or privilege so secured—
They shall be fined under this title or imprisoned not more than ten years, or both; and if death results from the acts committed in violation of this section or if such acts include kidnapping or an attempt to kidnap, aggravated sexual abuse or an attempt to commit aggravated sexual abuse, or an attempt to kill, they shall be fined under this title or imprisoned for any term of years or for life, or both, or may be sentenced to death.
death penalty would be icing on the cake, but 10 rs is a good start...