Hey Justiceseeker, thanks a lot for sharing. Indeed, it's a fascinating case.
The first time I heard about this case was when I was reading my
Encyclopedia of Unsolved Crimes, there's a small entry about the case in that book.
Like you said, in March 1994 DNA testing revealed that a link can be made between this case and the murder of 17 years old Melanie Bernas, in September of 1993. Melanie's body was found near the spot where Angela's head had been found. Biological evidence ( we don't know what kind ) found on both corpses is proof that both women wre killed by the same man. However the Killer's DNA profile has been entered into the National Database, but to this day no match was ever made.
Both cases are very strange. In both cases their bikes were stolen; is that the motive ?? Did the killer committed these horrible murders just to steal their bikes ?? Or was he keeping the bikes as souvenirs, or "treasures" ??
One important detail: The second victim's body, Melanie Bernas', was not decapitated or mutilated like Angela's body was. She had suffered stab wounds similar to the wounds Brosso suffered, but she wasn't decapitated, meaning that decapitation may not be part of the killer's MO or signature. It's very unusual to see a killer changing his MO like that, not impossible but unusual. It could possibly means that the man knew Angela and that he had personnal reasons to hurt her. I may be wrong, but that's how I see it. It's the only reason I see why he would decapitate a woman and not doing it to another.
There's always the possibility that Angela might have been decapitated by somebody else, or that the killer was rushed and didn't had enough time to decapitate or mutilate the body of Melanie, it's very possible.
The fact that, after all these years, no match were made is really really strange. Authorities have the killer's DNA, but still don't know his identity, it must be very frustrating for the families of the victims.