Illyrians

The Illyrians are a humanoid people whose culture is built around genetic engineering. They use it to adapt themselves to new planets and conditions instead of changing their surroundings, and some look human while others have visible differences. Because the Federation bans genetic modification, Illyrians have long faced suspicion and were kept out of Starfleet.
They first appeared in the Enterprise episode Damage, when Archer, desperate to complete his mission in the Delphic Expanse, takes the warp coil from an Illyrian ship. In Strange New Worlds, Commander Una Chin-Riley, the Enterprise's first officer, is secretly Illyrian. In Ghosts of Illyria, her nature lets her resist a disease from an abandoned Illyrian colony that infects the rest of the crew.
At the end of the first season she is arrested, and in Ad Astra per Aspera she stands trial for hiding her identity, defended by the Illyrian lawyer Neera Ketoul. The court accepts that she joined Starfleet as a form of asylum and acquits her.