1. Trial Commencement: The murder trial of Karl Jordan Jr. and Ronald Washington, accused of killing Run-DMC's Jam Master Jay over 20 years ago, is set to begin in Brooklyn federal court.

2. Charges and Pleas: Both defendants face murder charges, with prosecutors asserting their involvement in the 2002 shooting. Karl Jordan Jr. and Ronald Washington have pleaded not guilty.

3. Run-DMC Background: Jam Master Jay, born Jason Mizell, was a pivotal DJ for Run-DMC, a groundbreaking hip-hop group in the 1980s. His death, linked to a drug deal, led to the group's disbandment.

4. Case History: The murder case remained unsolved for many years until the arrest of Jordan and Washington in 2020. A third suspect, charged last year, will be tried separately.

5. Anti-Drug Stance: Despite Run-DMC's anti-drug stance in lyrics and public service announcements, prosecutors allege Jam Master Jay became involved in cocaine trafficking in the mid-1990s.

6. Drug Deal Dispute: Prosecutors claim that a drug deal dispute arose when Washington was cut out of a deal by Jay. This dispute led to the fatal encounter at Jay's recording studio in 2002.

7. Shooting Details: On October 30, 2002, Washington and Jordan, armed, entered the recording studio. Washington allegedly brandished a gun, ordering someone to the floor, while Jordan allegedly shot Jam Master Jay in the head.

8. Witness Testimonies: Witnesses, previously silent despite rewards, have now identified Washington and Jordan as the assailants, according to prosecutors. Washington has reportedly made statements corroborating his involvement.

9. Background of Suspects: Washington was previously named a suspect in 2007 but denied involvement. Jordan's defense cites family ties with Jay and claims he was at his girlfriend's home during the murder.

10. Charges and Potential Sentences: Jordan faces gun and cocaine charges in addition to murder. Both defendants could face at least 20 years in prison if convicted, as the government opts not to seek the death penalty.