NEWPORT NEWS, Va. — The case had gone cold. Four years after the 2007 murders of Christopher Horton, 16, and Brian Dean, 20, detectives here had little to go on. No suspects. No sign of the gun used to shoot the men. No witnesses to the shooting outside a house where officers found Mr. Horton sprawled next to a trash can and Mr. Dean on the front porch. But in 2011, the case was reassigned to a detective who later came across what he considered a compelling piece of evidence: a YouTube video of Antwain Steward, a local rapper with the stage name Twain Gotti, performing his song “Ride Out.” “But nobody saw when I [expletive] smoked him,” Mr. Steward sang on the video. “Roped him, sharpened up the shank, then I poked him, 357 Smith & Wesson beam scoped him.” Mr. Steward denies any role in the killings, but the authorities took the lyrics to be a boast that he was responsible and, based largely on the song, charged him last July with the crimes.
Today, his case is one of more than three dozen prosecutions in the past two years in which rap lyrics have played prominent roles. The proliferation of cases has alarmed many scholars and defense lawyers, who say that independent of a defendant’s guilt or innocence, the lyrics are being unfairly used to prejudice judges and juries who have little understanding that, for all its glorification of violence, gangsta rappers are often people who have assumed over-the-top and fictional personas. In some of the cases, the police say the lyrics represent confessions. More often, the lyrics are used to paint an unsavory picture of a defendant to help establish motive and intent. And, increasingly, the act of writing the lyrics themselves is being prosecuted — not because they are viewed as corroborating an incident, but because prosecutors contend that the words themselves amount to a criminal threat.