David Ray Hate Crimes Prevention Act of 2015 or David's Law

Amends the federal criminal code to impose penalties for willfully causing bodily injury to any person or, through the use of fire, a firearm, or an explosive device, attempting to cause such injury, whether or not acting under color of law, because of the actual or perceived race, color, religion, national origin, gender, sexual orientation, or disability of any person, where the offense is in or affects interstate or foreign commerce.

Directs the U.S. Sentencing Commission to study the issue of adult recruitment of juveniles to commit hate crimes and, if appropriate, to amend the federal sentencing guidelines to provide sentencing enhancements for such an offense.

Requires the Administrator of the Office of Juvenile Justice and Delinquency Prevention of the Department of Justice (DOJ) to make grants to state and local programs designed to combat hate crimes committed by juveniles.

Authorizes appropriations for the Department of the Treasury and DOJ for FY2015-FY2017 to increase the number of personnel to protect against criminal interference with federally-protected activities.