Short answers, pulled from the story.
Philadelphia rapper Schoolly D is generally considered the first gangsta rapper. His 1985 song "P.S.K. What Does It Mean?" is regarded as the first gangsta rap song, and it directly inspired Ice-T to create "6 in the Mornin'" in 1986, now regarded as the second gangsta rap song.
N.W.A's second album Efil4zaggin, released in 1991, was the first gangsta rap album to reach Number One on the Billboard pop charts. It was released after Ice Cube had already departed from the group.
Time Warner Music dropped Ice-T after controversy surrounding the Body Count song "Cop Killer" from the group's 1992 self-titled album. Critics including President George H.W. Bush, Vice President Dan Quayle, the National Rifle Association, and police organizations across the country objected to the song's content. Time Warner also refused to release Ice-T's planned follow-up album Home Invasion.
The simultaneous release of Kanye West's Graduation and 50 Cent's Curtis on the 11th of September 2007 is viewed as a turning point for hip-hop. West outsold 50 Cent by selling nearly a million copies in the first week, demonstrating that alternative hip-hop had secured commercial viability previously associated with gangsta rap.
The Supreme Court ruled in Elonis v. United States in 2015 that mens rea, meaning the intent to commit a crime, is necessary to convict someone for using threatening words in a rap song. A separate case involving rapper Jamal Knox reached the Supreme Court in April 2019, which declined to review his conviction for terroristic threats.
C. Delores Tucker, once the highest-ranking African American woman in the Pennsylvania state government, began campaigning against gangsta rap in 1993, labeling it "pornographic filth". She picketed stores that sold the music, circulated petitions, and bought stock in Time Warner, Sony, and other companies specifically to protest at shareholders meetings. She filed a $10 million lawsuit against Tupac Shakur's estate after he named her in tracks on his 1996 album All Eyez on Me; the case was eventually dismissed.