Criminologists and other social scientists should use their expertise to help the subjects of their research, including crime victims, says James Alan Fox, a professor of criminology, law, and public policy at Northeastern University.

Mr. Fox recently helped a 2012 master’s-degree graduate from Northeastern who was drawn into the aftermath of the Boston Marathon bombing. “Danny”—the pseudonym he adopted to protect himself from media hounding—became a hostage of the suspected bombers, the brothers Tamerlan Tsarnaev, 26, and Dzhokhar Tsarnaev, 19, who drove him around Cambridge, Mass., for 90 minutes, late at night, three days after the deadly attack.

Danny, a 26-year-old Chinese national who came to the United States in 2009 for graduate engineering studies, had just set up his own company. He had leased a new Mercedes. When he pulled over to reply to a text message, the brothers carjacked the vehicle, with him inside, at gunpoint.