Where 28 U.S.C. § 2462 permits tolling of 5-year statute of limitations by private agreement

QUESTION PRESENTED 1. Where 28 U.S.C. § 2462 provides in relevant part that, “[e]xcept as otherwise provided by Act of Congress, an action, suit or proceeding for the enforcement of any civil fine, penalty, or forfeiture, pecuniary or otherwise, shall not be entertained unless commenced within five years from the date when the claim first accrued...,” may the district court exercise subject matter jurisdiction over an action commenced more than five years after accrual of the claim, where the parties by private agreement purport to have tolled the five-year period? 2. May the district court enter a civil penalty in an SEC enforcement action that is more than 18 times the disgorgement amount (before interest), thereby exceeding the $150,000 cap set by Congress in 15 U.S.C. § 77t(d)(2), without contravening the Constitutional prohibition against excessive penalties reflected in the Court’s prior decisions?