Non-judicial punishment, also referred to as NJP, was a means by which a superior in a military service could discipline one of his/her juniors without convening a court-martial. Punishments could include reprimand, demotion, incarceration, loss of pay or privileges, extra duty, or restrictions.
In year 2371 of an alternate timeline, Veronica Stadi and Aman Evek ordered NJP against Celes Tal and Hogue Marritza respectively for an incident where the Cardassian officer had asked the Bajoran enlisted crew member to go hiking with him on Sikaris and she assaulted him. Both were verbally reprimanded and had shore leave, replicator, and holodeck privleges revoked. Celes was demoted to crewman apprentice, attached to the custodial team for six months, and was confined to quarters when off-duty. (The Mysterious Case of Neelix's Lungs: "Factoring Primes")