Contraband
The term contraband refers to items whose possession is criminalized by a government through restrictions placed on them. Such restrictions can range from a total ban to merely limiting possession of an item to authorized persons.

In 2152 an Enolian patrol ship intercepted , crewed by Jonathan Archer and Charles Tucker III, as it was leaving orbit of Keto-Enol. The Enolian crew boarded the shuttle and found what they believed was contraband, arresting Archer and Tucker in response. The crew of Archer's starship, , later proved their innocence. ()

In 2368, parts of a Vulcan navigational deflector were found in the Hanolin asteroid belt in a crashed Ferengi vessel. They were in crates marked "medical supplies", indicating that they were contraband. ()

In 2372, Quark smuggled a large quantity of kemocite, which was illegal in the Federation, to  in his newly acquired Ferengi shuttle Quark's Treasure while transporting his nephew Nog to Starfleet Academy. Upon discovering that the ship was sabotaged by  in an attempt to murder Quark, fellow passenger Rom used some of the kemocite to halt the destruction of the ship. It had the side effect, however, of throwing the ship back in time to the year 1947. After being detained by the United States Army, Rom was able to use the remaining kemocite to return to the 24th century. ()

Later that year, Kurn discovered contraband in the possession of the Boslic freighter captain Tilikia. However, Kurn deliberately allowed Tilikia to shoot him, wishing to end his life rather than live in dishonor. Kurn did not die, and Tilikia was arrested by Odo. ()

Also in that year, Kasidy Yates was arrested and sent to prison for smuggling contraband to the Maquis on her ship, the . ()

In 2380, Ensign Beckett Mariner brought a "big box" of contraband on board the  after shore leave on Douglas Station. () Mariner later told Ensign Bradward Boimler that Captain Riker of the  had provided her with a lot of her contraband over the years before Riker cut off the communications with the Cerritos.  Hearing that Deanna Troi remarked that she and her husband would talk about that later. ()

Examples of contraband

Items restricted in Federation space 
Bio-mimetic gel
Cloaking device – Federation research forbidden following Treaty of Algeron in 2311; also illegal in Bajoran space
Kemocite
Regalian liquid crystal
Remat detonator
Romulan ale
Romulan whiskey
Romulan mind probe
Artificial lifeforms (after the 2385 Attack on Mars)
Varon-T disruptor
Venus drug

Other restricted items 
Enolian spice wine
Maraji crystal – illegal in the Cardassian Union in 2336
Metagenic weapon – outlawed by most major interstellar governments in the 24th century
Mimetic simbiot – creation banned by the Lyssarian Prime Conclave
Rigelian flamegem – illegal in the Mutara sector in 2165 of an alternate timeline.
Skagaran whiskey – illegal on a former Skagaran colony in 2153
Tallonian crystal – illegal anywhere but on the Tallonian homeworld
Thought maker – illegal in the Ferengi Alliance in 2364
Subspace weapons – banned by the Second Khitomer Accords

External link 
 
Crimes