Voletta Wallace has never stopped searching for answers about the night her son, Biggie Smalls, was killed and now on the 20th anniversary of his death, she says she knows who murdered him and she thinks the LAPD does too.

On March 9, 1997,  rapper Christopher Wallace a.k.a. the Notorious BIG was gunned down in a drive-by shooting leaving an after party in Los Angeles.

There have been several conspiracy theories over the years about who killed Biggie. Many believe it was a revenge killing for the murder of his former friend turned rival rapper, Tupac Shakur, months earlier and that the hit was ordered by former Death Row mogul Suge Knight. Others believe that Biggie's closest pal, P. Diddy a.k.a. Sean Combs, had something to do with the killing for reasons not known. However, no one has ever been charged with the murder and Wallace is just left to deal with the hurt from losing her son everyday.

She told that Daily Mail that she and the LAPD detectives who worked on the case know who killed her son but at least one conspiracy prevents the murder from being solved and Biggie's killer being brought to justice.

"I have a very good idea who murdered Christopher and I genuinely believe that the LAPD knows exactly who did too," Voletta said from her home in Stroudsburg, Pennsylvania. "They’ve done their investigation, but they just refuse to move forward. I don’t know why they haven’t arrested who was involved. It seems to me that it’s one giant conspiracy and someone is definitely being protected somewhere down the line."

The same may be said for the murder of Tupac, who died on Sept. 13, 1996. To this day both crimes remain unsolved and the colder these cases get it seems less and less likely that we will ever know who killed either one of these incredible rappers.