Suge Knight
There are theories that Suge Knight, the CEO of Death Row Records — the man in the driver's seat when Tupac got shot — could have had something to do with either death. People believe he wanted Tupac dead so he wouldn't switch record labels, or that he had Biggie killed out of revenge for Tupac's murder. Or that he had Biggie killed to distract investiagtors from pointing the blame for Tupac's death in his direction.
In January 2015, Knight was arrested after a hit-and-run in Los Angeles. He was charged with one count of murder, one count of attempted murder, and two counts of hit-and-run. If he's convicted, he potentially faces life in prison.