At the center of the cases was Maryland's 6th district which historically favored Republicans and which was redrawn in 2011 to shift the political majority to become Democratic via vote dilution.

[1] Affected voters filed suit, stating that the redistricting violated their right of representation under Article One, Section Two of the U.S. Constitution and freedom of association of the First Amendment.

The state challenged this in Lamone v. Benisek, which the Supreme Court heard in the 2018–2019 term alongside Rucho v. Common Cause, a partisan redistricting case from North Carolina.

Democratic analysts envisioned the possibility of an "8–0 map" which aspired to shut Republicans out of elections altogether; however, this may have endangered some incumbents, who rejected the proposal because they wanted to stay in office more easily.

The state Democrats drew on services from the National Committee for an Effective Congress (NCEC) to determine how to create this "7–1 map".

Previously it had covered most of the rural northwestern part of the state along the Pennsylvania border and was a predominantly Republican district with a largely Caucasian population that had supported Representative Roscoe Bartlett for two decades.

After redistricting, the 6th district still covered the western arm of the state, but now also included many of the suburban and metropolitan areas across the border from Washington D.C., thereby increasing the number of African-American voters within it.

[10] The case, filed as Benisek v. Mack, was reviewed by Judge James K. Bredar who deemed that none of the complaints brought by the plaintiffs were actionable and denied the request for a standard three-judge hearing in April 2014.

Judge Bredar did find that the case represented a substantially different subset of residents than Fletcher and rejected the defense's argument for res judicata.

In response to the plaintiffs' arguments, Judge Bredar found that the plaintiffs did not provide an effective measure to demonstrate partisan gerrymandering as suggested by Vieth v. Jubelirer, thereby nullifying their Article One and 14th Amendment claims, and that the affected citizens still had their rights to participate in the political process intact, thus denying any relief based on the 1st Amendment claim.

[13] The case, Shapiro v. McManus, was accepted by the Supreme Court in June 2015, with oral arguments heard in November 2015 and the decision issued in December 2015.

The plaintiffs had revised their case to focus specifically on the redrawn boundaries of the 6th district, which had had the greatest shift in voter demographics.

[28] The case was decided on June 27, 2019; a 5–4 majority determined that claims of partisan gerrymandering present a nonjusticiable political question that could not be handled by the federal court system.