RICHMOND, Va. (AP) — Federal judges have appointed a special expert to help redraw Virginia’s state legislative districts.

A three-judge panel appointed Bernard Grofman, an economics and political science professor at the University of California, Irvine, on Thursday. Judges also said indicated they want a new map to be in place by March 28, 2019.

A federal court ruled this summer that lawmakers illegally packed black voters into 11 districts and ordered lawmakers to draw a new map by the end of this month.

That’s unlikely to happen. Democratic Gov. Ralph Northam has said the court was best positioned to draw a new map and has promised to veto Republican-drawn maps.

Grofman was picked by judges in 2015 to help redraw the state’s congressional districts.