Nathaniel Taquan Mangrum, a 31-year-old Black man from Wilmington, Delaware, was killed during a burst of gunfire inside the Shades of Blue Bar and Grill on Governor Printz Boulevard shortly after midnight on April 1, 2016. The shooting was reported at approximately 12:39 a.m., drawing Delaware State Police and officers from several other agencies to the crowded bar and its parking lot.
Investigators learned that two patrons had been shot inside before the gunman fled.
Mangrum was treated at the scene by New Castle County paramedics and flown by state police helicopter to Christiana Hospital, where he was pronounced dead. Another patron was taken to a hospital in a private vehicle and treated for injuries that were not considered life-threatening. Prosecutors later said the gunman first shot that patron, then approached Mangrum and fired at him once before shooting him two more times as he lay on the floor. Mangrum died a short time later.
By the evening of the shooting, detectives had identified Wilmington resident Tyerin A. Griffin as the suspect. Police obtained warrants charging Griffin with first-degree murder, attempted first-degree murder and two firearm offenses. Authorities said he had ties to both Wilmington and Philadelphia, and the search for him continued for several months.
On September 4, 2016, Griffin surrendered to detectives at Delaware State Police Troop 1 in Penny Hill. He was formally charged with first-degree murder, attempted first-degree murder, possession of a firearm during the commission of a felony and possession of a firearm by a person prohibited. After his arraignment, he was committed to the Howard R. Young Correctional Institution without bail. A New Castle County grand jury later indicted him on first-degree murder, attempted first-degree murder, three firearm counts, first-degree reckless endangering and possession of a firearm by a person prohibited.
Griffin went to trial in Superior Court, where he argued that he had acted in self-defense. After a five-day proceeding, the jury rejected a complete self-defense acquittal but convicted him of manslaughter under an extreme-emotional-distress theory, a lesser offense included within the original murder charge. He was also convicted of first-degree reckless endangering and two counts of possession of a firearm during the commission of a felony. In a separate bench proceeding, the judge found him guilty of possessing a firearm while legally prohibited from doing so. The attempted-murder allegation did not result in a conviction; the shooting of the surviving victim was addressed through the reckless-endangering and firearm verdicts.
Because Griffin had prior felony convictions involving drugs and robbery, he was sentenced as a habitual offender. The court imposed an aggregate sentence of 90 years in prison. His convictions and sentence were upheld on direct appeal in March 2020 after the Delaware Supreme Court rejected his argument that the trial judge had inadequately instructed jurors on self-defense in relation to the manslaughter charge.
Griffin later challenged the sentencing law used in his case. The state agreed that the original sentence had been imposed under the wrong version of Delaware's habitual-offender statute, but the correction did not reduce his time in prison. In December 2021, the Superior Court resentenced him under the law that had been in effect when the shooting occurred and again imposed a total of 90 years. The Delaware Supreme Court affirmed that resentencing in August 2022, leaving the convictions and prison term in place.
