He called the redistricting maps a "dramatic change that was accomplished through ever more systematic tracking and packing of Democratic voters.”

Stephanopoulos outlined a three-pronged case focused on "discriminatory intent," "discriminatory effect" and "justification." His case relies largely on a mathematical test called "the efficiency gap" to look at whether the districts allow votes for Republicans and Democrats to have equal weight.

Assistant Attorney General Brian Keenan criticized the "efficiency gap," which issues scores to each districts predicting which party will win them. Keenan said the metric's calculations were not correct and was not a valid way to predict the outcome of elections.

The scores “are far from magic crystal balls that predict the future,” he said. "These are just educated guesses."

How legislative districts are drawn are often predictive of which party's candidates can win there. Districts with higher concentrations of Republican voters will increase the likelihood that a Republican will win that district and gain a seat in the Legislature. Critics of the current legislative map say Republicans purposefully parsed the state along partisan lines with the aim to create more districts that Republicans can win.