USA Today reports:
"An independent watchdog group is filing an ethics complaint against several House Democrats for violating House rules last week during lawmakers' 25-hour sit-in to demand votes on gun control. The Foundation for Accountability and Civic Trust, a conservative-leaning ethics watchdog group, filed a complaint with the House Office of Congressional Ethics on Monday arguing that lawmakers violated ethics rules by fundraising around specific legislation and by using House resources for political purposes...."
Read more at http://www.usatoday.com/story/news/politics/2016/06/27/house-democrats-face-ethics-complaints-fundraising-off-sit-/86437224/ Paul Singer, the author of the piece, also wrote an opinion piece on the subject lamenting the press involvement.
The House ethics manual is online. Additionally, the Congressional Research Service has a very useful report on the House Office of Congressional Ethics: "House Office of Congressional Ethics: History, Authority, and Procedures." It explains:
"The mandate of the OCE, which has jurisdiction only in the House, is to review information, and when appropriate, refer findings of fact to the House Committee on Ethics. Only this committee, pursuant to House rules, has the authority to recommend House discipline of Members and staff. Information of alleged wrongdoing by Members, officers, and employees of the House may be accepted by the OCE from the general public, but only the OCE board can initiate a review. The OCE is composed of six board members, and at least two alternates, each of whom serves a four-year term. The Speaker and the minority leader are each responsible for the appointment of three board members and one alternate. The chair is selected by the Speaker and a co-chair is selected by the minority leader."
How the incident will play out is unclear. Ethics investigations usually take a great deal of time, and any discipline that could come would heighten tensions between the parties and further complicate legislating. The House Committee on Ethics' membership, it is worth noting, comprises five Republicans and five Democrats.