A Maryland circuit court judge Friday struck down the state’s new congressional district map, calling it an “extreme gerrymander.”

The new district map was drawn by the Democratically-controlled state general assembly last year but was vetoed by Republican Governor Larry Hogan. That same day the general assembly overrode Hogan’s veto and enacted the map. Maryland has eight congressional districts, seven of which are traditionally Democrat and one Republican. Under the new map, the lone Republican district would become a hypercompetitive district.

Two groups of plaintiffs sued, alleging that the map violated the state constitution, and their cases were consolidated. In her opinion, senior judge Lynne Battaglia noted that the testimony presented in the case supported the notion that Republican voters’ voices had been diluted and diminished by the Democratic map and that “no compelling reason for the dilution and diminution was ever adduced by the State.” She concluded that the map was unconstitutional and subverted the “will of those governed.”

Fair Maps Maryland, an anti-gerrymandering group that backed one of the lawsuits, issued a statement calling Maryland “ground zero for gerrymandering” and hailed the ruling as “a win for democracy, plain and simple.” Judge Battaglia ordered the general assembly to redraw the map by March 30 and scheduled a hearing about the redrawn map for April 1.