A Manhattan grand jury has indicted hapless Harlem-born rapper "G-Dep for the 1993 murder that he inadvertently confessed to earlier this month. The P-Diddy protégé has now gone from being a free man -- once unsought in the cold-case shooting -- to a no-bail defendant facing a maximum possible prison term of 25 years to life. "He was making amends," said G-Dep's lawyer, Michael Alperstein, explaining his client's confession to the fatal shooting. Alperstein said the rapper's admission was prompted by a 12-step narcotics program. Last week, G-Dep -- whose real name is Trevell Coleman -- was catapulted to a fame that he never enjoyed in hip-hop after confessing to a cold-case shooting, only to be shocked to learn that his alleged victim had died.