Walter Scott Notification Act of 2017 This bill requires a state that receives funding under the Edward Byrne Memorial Justice Assistance Grant (JAG) program to report certain data on deadly shootings by law enforcement officers. It reduces by 10% the JAG allocation of a state that fails to comply. Additionally, the bill amends the Omnibus Crime Control and Safe Streets Act of 1968 to modify requirements under the Community Oriented Policing Services (COPS) program. During the four-year period following enactment, the Department of Justice (DOJ) may give preference to a COPS program grant applicant from a state that reports data on deadly shootings by law enforcement. Beginning in the fifth year, DOJ must reduce by 20% the COPS allocation of a state that fails to report such data. DOJ, in coordination with the Federal Bureau of Investigation, must issue guidance to standardize data collection on deadly shootings by law enforcement. DOJ must also audit and review data reports, determine compliance with requirements, and publish such data.