Syrian War Crimes Accountability Act of 2017 (Sec. 3) This bill: (1) condemns the violence and human rights violations carried out by the Syrian government and pro-government forces; (2) urges all parties to halt civilian attacks; (3) expresses support for the people of Syria seeking democratic change; and (4) calls on the President to support efforts to ensure accountability for war crimes, crimes against humanity, and genocide committed during the conflict in Syria. (Sec. 5) The Department of State shall report to Congress regarding: (1) war crimes, crimes against humanity, and genocide committed in Syria; and (2) an assessment by the State Department's Office of Global Criminal Justice, the U.S. Agency for International Development, the Department of Justice, and other agencies with respect to U.S. programs to ensure accountability for such activities by the regime of President Bashar al-Assad, violent extremist groups, and other combatants. The State Department shall take due care to ensure that the identification of witnesses and physical evidence are not publicly disclosed in a manner that might place such persons at risk or encourage the destruction of evidence. (Sec. 6) The State Department shall: (1) complete a study of the feasibility of potential transitional justice mechanisms for Syria (including a hybrid tribunal) to address war crimes, crimes against humanity, and genocide perpetrated in Syria beginning in March 2011; and (2) include in the report on such study recommendations on which transitional justice mechanisms the U.S. government should support, why, and how. (Sec. 7) The State Department may provide assistance to entities that: (1) identify suspected perpetrators (including non-state armed groups) of war crimes, crimes against humanity, and genocide; (2) collect and protect evidence of crimes; (3) conduct criminal investigations; (4) protect witnesses; or (5) build Syria's investigative, enforcement, and judicial capacities. The State Department also may provide assistance to support the creation and operation of transitional justice mechanisms. (Sec. 8) The bill authorizes the State Department to make payments, under the Rewards for Justice Program, for information leading to the arrest or conviction of perpetrators of war crimes, crimes against humanity, and genocide committed in Syria beginning in March 2011. (Sec. 9) The bill calls for the State Department to advocate that the United Nations Human Rights Council, while the United States remains a member, annually extend the mandate of the Independent International Commission of Inquiry on the Syrian Arab Republic until the commission has completed its investigation of alleged violations of international human rights laws in Syria beginning in March 2011.