Seizure of private property because it was illegally obtained, is an illegal substance or the legal basis for possession has ended.
In Connellan v. Federal Life & Casualty Co., 134 ME 104, 1935, the Supreme Judicial Court of Maine adopted these words:
"Forfeiture is deprivation or destruction of a right in consequence of the non- performance of some obligation or condition."
Forfeiture is a legal concept well known to the common law as it was a preferred technique for British royals to pad their coffers: until 1870, anybody convicted of a felony in England forfetited all their property to the Crown!
Blackstone, in his Commentaries on the Laws of England, dedicated an entire chapter to "Title by Forfeiture", which he defined as:
"Forfeiture is a punishment annexed by law to some illegal act, or negligence in the owner of lands and tenements, whereby he loses all his interest therein, and they go to the party injured, as a recompense for the wrong which either he alone, or the public together with himself, have sustained."
In some cases, forfeiture may occur as between individuals such as where a jurisdiction allows for the forfeiture of a lease in the event of nonpayment of rent.
However, in most cases, forfeiture is undertaken by the state. Property is usually subject to forfeiture to the state if it was purchased using illegally obtained money, used during the commission of a crime or a prohibited activity, or if the property was stolen.
For example, Canada's Aeronautics Act, at s. 7.4 states that:
"Where a person is convicted ... of (a specific) offence ... in relation to the operation of a commercial air service, the court may, in addition to any other punishment it may impose, order that any aircraft used in the commercial air service be forfeited and, on the making of such an order, the aircraft is forfeited to Her Majesty in right of Canada."
The US Code also provides for forfieture in criminal matters as set out at s. 3681 of Title 18, Chapter 232A:
"Upon the motion of the United States attorney made at any time after conviction of a defendant for an offense under section 794 of this title (gathering or delivering defense information to aid foreign government) or for an offense against the United States resulting in physical harm to an individual, and after notice to any interested party, the court shall, if the court determines that the interest of justice or an order of restitution under this title so requires, order such defendant to forfeit all or any part of proceeds received or to be received by that defendant, or a transferee of that defendant, from a contract relating to a depiction of such crime in a movie, book, newspaper, magazine, radio or television production, or live entertainment of any kind, or an expression of that defendant’s thoughts, opinions, or emotions regarding such crime."