Student Disciplinary Fairness Act of 2017 This bill amends the Juvenile Justice and Delinquency Prevention Act of 1974 to establish within the Department of Justice (DOJ) an Office of School and Discipline Policy to reduce the number of juveniles who are incarcerated and develop a criminal history based on activity that occurs at school. The bill amends the Omnibus Crime Control and Safe Streets Act of 1968 to require applicants for grants under the Community Oriented Policing Services program to provide assurances that the administration of juvenile justice in their jurisdictions is consistent with constitutional guarantees, including due process and equal protection, and that probation terms for a juvenile meet certain conditions. It amends the Violent Crime Control and Law Enforcement Act of 1994 to authorize DOJ to issue subpoenas during investigations of law enforcement agencies for alleged patterns or practices of conduct that violate constitutional rights. Finally, the bill directs the Department of Education's Office of Civil Rights to make grants to states, local governments, and juvenile justice agencies to train teachers and administrators on de-escalation techniques to mitigate delinquent student behavior.