Sunshine for Regulatory Decrees and Settlements Act of 2017 This bill establishes public notice and comment procedures and motion to intervene standards for civil actions seeking to compel agency action and alleging that an agency is unlawfully withholding or unreasonably delaying an agency action, and for consent decrees or settlement agreements that require agency action, relating to a regulatory action that would affect the rights of: (1) private persons other than the person bringing the action; or (2) a state, local, or tribal government. The bill sets forth requirements for: agencies against which such an action is brought to publish online, within 15 days after receipt, the notice of intent to sue and the complaint; courts to consider motions to intervene and allow amicus participation; and any settlement proceedings to include intervening parties and to be conducted pursuant to the mediation or alternative dispute resolution program of the court or by a district judge. Agencies seeking to enter such a consent decree or settlement agreement must: publish, and accept and respond to public comment on, the proposed agreement or decree for 60 days before filing it with the court; and make available to the court the administrative record and a summary of public comments and any public hearings. The Department of Justice, or an agency litigating a matter independently, must certify to the court its approval of such proposed: (1) consent decrees that include terms that convert into a nondiscretionary duty a discretionary authority of an agency to propose, promulgate, revise, or amend regulations, commit an agency to expend funds that have not been appropriated and budgeted or to seek a particular appropriation or budget authorization, divest an agency of discretion committed to it by statute or the Constitution, or otherwise afford any relief that the court could not enter under its own authority; or (2) settlement agreements that include terms that provide a remedy for a failure by the agency to comply with the terms of the agreement other than the revival of the civil action resolved by the agreement, interfere with the authority of an agency to revise, amend, or issue rules, or commit the agency to expend funds that have not been appropriated and budgeted or to exercise in a particular way discretion which was committed to the agency by statute or the Constitution. Courts: (1) shall not approve such consent decrees or settlement agreements unless they allow sufficient time and procedures to comply with the Administrative Procedure Act, rulemaking statutes, and executive orders; and (2) shall grant de novo review if an agency files a motion to modify such a decree or agreement on the basis that its terms are no longer fully in the public interest due to changed facts and circumstances or the agency's obligations to fulfill other duties.