Former Massachusetts State Senate President Stan Rosenberg will resign his Amherst-based seat 5 p.m. Friday.

Rosenberg's decision to exit comes almost 24 hours after the Senate Ethics Committee issued a harsh review of Rosenberg's failure to protect the integrity of the Senate and the physical well-being of Senate members and their staffs from his husband, Bryon Hefner, who investigators found to be a sexual predator who sought to trade influence — bogus though that may have been — for favors.

By mid-morning today, five Democrats called upon Rosenberg to resign.

Senate President-in-waiting Karen Spilka may have pushed Rosenberg over the edge.

"Because Senator Rosenberg allowed a destructive pattern of behavior to continue over the course of many years, violating the trust that my colleagues and I invested in him, it is my firm belief that he should resign," Spilka said in a written statement.

Currently Ways and Means Chair, Spilka owed her leadership position to Rosenberg's sponsorship.

Her public censure carried weight.

Governor Charlie Baker and Attorney General Maura Healey yesterday called for Rosenberg to leave the Senate for good.

The Senate is scheduled to begin its budget deliberations May 10, Rosenberg's exit clears the floor of what now becomes an extraneous matter.