Is gerrymandering unconstitutional?

Gerrymandering, or drawing legislative and congressional district lines to benefit the party in power, has been a political tactic since the 1800s. But as the nation grows more entrenched in party lines and gerrymandering gets more extreme with the help of technology, the question of how to draw voting districts has drawn a lot of attention. The Supreme Court recently sent two gerrymandering cases from Wisconsin and Maryland back to the lower courts, but as 2020 redistricting time looms closer, people are wondering whether partisan gerrymandering is constitutional.