A timeline of court rulings and evolving regulations that have affected how schools respond to student sex assault allegations:


The Office for Civil Rights is created as a federal agency to enforce school desegregation, three years after passage of the Civil Rights Act. OCR eventually assumes responsibility for a half-dozen civil rights laws at educational institutions receiving federal funding.


Congress passes Title IX, which prohibits sex discrimination in federally funded education programs or activities.


The 2nd U.S. Circuit Court of Appeals, in Alexander v. Yale University, recognizes sexual harassment as a form of sex discrimination prohibited by Title IX.


The OCR issues a policy memo that, for the first time, lists sexual harassment as a form of discrimination under Title IX.


The U.S. Supreme Court, in Franklin v. Gwinnett County Public Schools, says a student subjected to “coercive intercourse” is a victim of sex discrimination, eligible for monetary damages under Title IX.


OCR issues sexual harassment guidance for schools on how to deal with victims and suspects, detailing grievance procedures, response, prevention and First Amendment rights.


The U.S. Supreme Court, in Gebser v. Lago Independent School District, establishes a three-prong liability standard for schools: The sexual harassment must be severe enough to undercut educational opportunities, someone in authority must have “actual knowledge” of the harassment and be “deliberately indifferent” in responding.


The U.S. Supreme Court, in Davis v. Monroe County Board of Education, affirms that schools must address student-on-student sex harassment, including sexual assault, under Title IX.


OCR updates its 1997 guidance on Title IX, saying schools risk losing federal funding if they don’t follow the guidelines for investigating student sexual harassment complaints.


In a letter to more than 20,000 school districts, colleges and universities, OCR reiterates their Title IX responsibilities to stop student sexual harassment, prevent its recurrence and remedy its effects.


OCR publishes a pamphlet noting that sexual harassment includes “criminal” conduct and that schools are not relieved of Title IX obligations simply by notifying police.


The White House Council on Women and Girls is created by executive order to focus on issues ranging from equal pay to violence. OCR begins tracking sexual violence complaints as a distinct form of harassment.


OCR issues another letter , focusing on student-on-student sexual violence. It recommends schools use a civil litigation standard of proof in investigating cases and warns of lost federal funding if they fail to prevent and address such abuse.


The Council on Women and Girls creates a task force to protect students from sexual assault and a website of resources. OCR issues further guidance on the Title IX responsibilities of all schools, elementary to university level.


The task force launches an online toolkit for elementary and secondary school districts that helps create policies that distinguish “sexual misconduct” from bullying and harassment.