Nassau County legislators voted to approve new legislative district lines on Monday.
The new map had the support of the Republican majority in the Nassau Legislature, but the minority party says the map isn't fair.
Democrat Kevan Abrahams accuses Republicans of drawing lines that favor their own party.
He says the new map violates the John Lewis Voting Rights Act because it does not create five mostly minority districts.
"The communities of Freeport, Lakeview, you name it, have all come down, have asked for certain things to be incorporated into the map and they're just not going to do it," Abrahams says.
Republican leader Richard Nicolello says the map is fair and creates competitive legislative districts that could be represented by Democrats or Republicans.
"This map is not gerrymandered to favor Republicans," Nicolello says. "Any of these districts could flip one way or the other."
The district lines will remain in place for the next 10 years.
The new map has to be approved by March 7, meaning Nassau County Executive Bruce Blakeman has to sign off on it.