For example, if a sitting member of congress ("She") misleads the public on a TV news interview regarding the fiscal impact of proposed legislation. If the lie would adversely impact the taxes paid (or decrease income received) by certain constituents of her district, or increase the national debt, might those constituents file suit claiming fraud or negligent misrepresentation?
Extending that, if She first secretly works with an identifiable official of the executive branch ("He") to further such deception of the public. If He then commits an overt official act (in violation of official policy or the Hatch Act) and She later admits her participation (on TV) while still misleading the public. Would that demonstrate conspiracy actionable by constituents?
Who has the standing to raise such concerns in civil court? Might stockholders in a corporation in the representative's district who are particularly disadvantaged by the legislative goals of the misrepresentation have standing? Would such standing be reserved to those She represented directly?
Clarifications after further research
Please assume that either Washington State and Federal rules could apply. Based on an otherwise good answer, I've updated the original question to change "fraud" to "fraud or negligent misrepresentation". I add this with the understanding that the latter is when a person does not lie directly but has made a statement about a subject with no reason to believe it to be fact.
I posit that both government employees have a pecuniary interest in the passage of partisan legislation through their employment salary and campaign contributions. In addition, their future revenue as consultants might be at stake. How might "special duty to disclose" apply?
I'm assuming that neither She nor He is appropriately acting within their official capacity, but they are operating under the color of law. I think there's some Latin phrase for that, but I don't remember it.
I suggest the potential harm could be realized imminently by the passage of legislation. Both government employees should well know the potential for such harm, but fail to mention it publicly, and that omission is at the heart of the deception. They take care to hide it.
Could stockholder-constituents use civil rights law without demonstrating actual particularized financial harm?
Gravel v. the United States (408 US 618, 1972[?]) seems to provide some related guidance and citations re the Speech or Debate Clause of the Constitution. I recognize the specific circumstances of Gravel are inapplicable; I'll leave it up to more experienced members to find more appropriate authorities and determine how this would apply to my hypothetical civil action.
I'd also welcome any speculation about how an individual might act to mitigate my (hypothetical) representative's conduct. Please assume they are not looking for personal gain but to seek disgorgement of any income the representative or her campaign might obtain by way of said deception(s). The primary motive I posit is to block the legislation.
Would it be necessary to precisely identify any controversial income to raise this in civil court?
If successful, might reasonable attorneys fees be recovered? Would this be something a reasonable attorney might take up somehow without costing an individual stockholder-constituents an arm and a leg? Could this make a good class-action case?