Question:  Robert "Bobby" DeLaughter is a prosecutor, judge, and author notable for prosecuting and securing the conviction of a white supremacist and Klansman who was convicted of assassinating what civil rights leader?   
Context: Samuel Holloway Bowers (August 25, 1924 – November 5, 2006), Former Ku Klux Klan Imperial Wizard, was a convicted murderer and leading white supremacist activist in Mississippi during the Civil Rights Movement.  In response to this movement, he co-founded a reactionary organization, the White Knights of the Ku Klux Klan.  Bowers committed two notorious murders of civil rights activists in southern Mississippi: The 1964 murders of Chaney, Goodman, and Schwerner near Philadelphia, for which he served six years in federal prison; and the 1966 murder of Vernon Dahmer in Hattiesburg, for which he was sentenced to life in prison 32 years after the crime.  He also was accused of bombings of Jewish targets in the cities of Jackson and Meridian in 1967 and 1968 (according to the man who was convicted of some of the bombings, Thomas A. Tarrants III).  He died in prison at the age of 82. Jamie Kelso (June 8, 1948) is an American white supremacist and former Church of Scientology member of the elite Sea Org.  He hosts daily web radio programs, including "The Jamie Kelso Show" on the Voice of Reason Broadcast Network, and is a senior moderator of the white supremacist Stormfront website, where he uses the name Charles A. Lindberg.  Kelso became a moderator at Stormfront in 2002 and was instrumental in its rapid growth, partially by encouraging senior figures in the white supremacist movement to post. Medgar Wiley Evers (July 2, 1925June 12, 1963) was an American civil rights activist from Mississippi who worked to overturn segregation at the University of Mississippi and enact social justice and voting rights.  He was murdered by a white supremacist and Klansman. David Eden Lane (November 2, 1938 – May 28, 2007) was an American white supremacist leader and convicted felon.  A member of The Order, he was convicted and sentenced to 190 years in prison for racketeering, conspiracy, and for violating the civil rights of Alan Berg, a Jewish radio talk show host, who was murdered on June 18, 1984.  He died while incarcerated in the Federal Correctional Complex in Terre Haute, Indiana. Frederick Paul Fromm (born January 3, 1949), known as Paul Fromm, is a Canadian white supremacist and perennial candidate based in Mississauga, Ontario.  Fromm is the international director of the white supremacist organization Council of Conservative Citizens.  He has hosted a radio show on the Stormfront web site and has ties to former Ku Klux Klan members David Duke, Don Black, and Mark Martin (a white supremacist rally organizer in Covington, Ohio).  The "National Post" newspaper described him as "one of Canada's most notorious white supremacists." Bobby Frank Cherry (June 20, 1930 – November 18, 2004) was an American white supremacist and Klansman who was convicted of murder in 2002 for his role in the 16th Street Baptist Church bombing in 1963.  The bombing killed four young African-American girls (Carole Robertson, Cynthia Wesley, Addie Mae Collins, and Denise McNair) and injured more than 20 other people. Robert "Bobby" DeLaughter (born February 28, 1954) is an American Mississippi state prosecutor, judge, and author.  He is notable for prosecuting and securing the conviction in 1994 of Byron De La Beckwith, charged with the murder of the civil rights leader Medgar Evers on June 12, 1963.  Two earlier trials in Mississippi in 1964 had resulted in hung juries. Identity Evropa is a white supremacist group in the United States, established in March 2016.  Part of the broader white supremacist alt-right movement, the group is identified as a racist white supremacist organization by the Anti-Defamation League and is designated by the Southern Poverty Law Center as a hate group.  Relatively small in size, the group is seen as one of several groups contributing to a rising spike of white nationalism in the U.S. since 2015.  The group particularly targets college campuses, by distributing white nationalist slogans on fliers, posters, and stickers. Byron De La Beckwith, Sr. (November 9, 1920 – January 21, 2001) was an American white supremacist and Klansman from Greenwood, Mississippi, who in 1994 was convicted of assassinating civil rights leader Medgar Wiley Evers on June 12, 1963.  Two previous trials in 1964 on this charge had resulted in hung juries.  Seven years after being convicted of killing Evers, De La Beckwith died in prison in 2001 at the age of 80 while serving a life sentence. Richard Bertrand Spencer (born May 11, 1978) is an American white supremacist.  He is president of the National Policy Institute, a white supremacist think tank, as well as Washington Summit Publishers.  Spencer has stated that he rejects the label of white supremacist, and prefers to describe himself as an identitarian.  He has advocated for a white homeland for a "dispossessed white race" and called for "peaceful ethnic cleansing" to halt the "deconstruction" of European culture.
Answer: Medgar Wiley Evers