In law, aiding and abetting was the act of being a knowing accomplice, but not necessarily an active participant, in someone else's intent to commit a crime.
While attempting to destroy Landru with logic, Lieutenant Commander Spock inquired if the computer was "aiding the Body, or [..] destroying it?" (TOS: "The Return of the Archons")
In 2366, the Klingon High Command belatedly accused Mogh of "aiding and abetting the Romulan attack on the Khitomer Outpost." Had the charge been upheld by the High Command, the family name of the House of Mogh would have been disgraced for seven generations, with the family getting its first chance of returning to grace in the 27th century. (TNG: "Sins of The Father")
Later that year, following the discovery of two apparent survivors of the annihilated Federation colony on Rana IV, Captain Jean-Luc Picard wondered aloud if they were perhaps collaborators or "did they provide the colony's assailants with something that abetted the total destruction of Rana IV in order to protect their own lives?" (TNG: "The Survivors")
In 2366, Klingon Ambassador Kell informed Captain Picard that Vagh, the Governor of Krios, had charged that the Federation was secretly aiding the Kriosian rebels. (TNG: "The Mind's Eye")
In 2370, Chief Archon Makbar presented at the tribunal against Miles O'Brien, that he had "been found guilty of aiding and abetting seditious acts against the state." For his actions, he was sentenced to death. (DS9: "Tribunal")
In 2372, Tom Paris and Harry Kim from USS Voyager were accused of aiding the Akritirian terrorist group known as "Open Sky". For their crime, they were sentenced to an Akritirian maximum security detention facility. (VOY: "The Chute")
When it was discovered, in 2375, that the Federation Council had both the means and the cure for the morphogenic virus that Section 31 used to infect the Changelings, Captain Benjamin Sisko revealed to Odo that they had "considered giving the Founders the cure, then they decided against it." Odo described those actions as "abetting genocide." (DS9: "The Dogs of War")
In 2377, after Harry Kim assisted a damaged Kraylor medical transport, Captain Kathryn Janeway informed him that he had put her in "a difficult position," with their new colleagues, the Annari, who were at war with the Kraylor, because Kim's actions might be perceived as "aiding their enemy." (VOY: "Nightingale")
Later that year, after The Doctor was kidnapped by the hologram Iden, and asked to join his rebellion, his captor declined, stating that "my program doesn't include aiding and abetting murderers." (VOY: "Flesh and Blood")