House demolitions, leveling of agricultural land and expropriation of land are violations of Articles 33 and 53 under the Fourth Geneva Convention and is furthermore defined as a grave breach under article 147 and thus constitutes a war crime. In addition, the UN Committee Against Torture has found, that the Israeli government's house demolition policy "may, in certain instances, amount to cruel, inhuman or degrading treatment or punishment" in violation of Article 16 of the UN Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment. [1]

The Fourth Geneva Convention

Art. 33. No protected person may be punished for an offence he or she has not personally committed. Collective penalties and likewise all measures of intimidation or of terrorism are prohibited.

Pillage is prohibited.

Reprisals against protected persons and their property are prohibited.

Art. 53. Any destruction by the Occupying Power of real or personal property belonging individually or collectively to private persons, or to the State, or to other public authorities, or to social or cooperative organizations, is prohibited, except where such destruction is rendered absolutely necessary by military operations.

Art. 147. Grave breaches to which the preceding Article relates shall be those involving any of the following acts, if committed against persons or property protected by the present Convention: wilful killing, torture or inhuman treatment, including biological experiments, wilfully causing great suffering or serious injury to body or health, unlawful deportation or transfer or unlawful confinement of a protected person, compelling a protected person to serve in the forces of a hostile Power, or wilfully depriving a protected person of the rights of fair and regular trial prescribed in the present Convention, taking of hostages and extensive destruction and appropriation of property, not justified by military necessity and carried out unlawfully and wantonly.
 

UN Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment

Article 16

1. Each State Party shall undertake to prevent in any territory under its jurisdiction other acts of cruel, inhuman or degrading treatment or punishment which do not amount to torture as defined in article 1, when such acts are committed by or at the instigation of or with the consent or acquiescence of a public official or other person acting in an official capacity. In particular, the obligations contained in article 10, 11, 12 and 13 shall apply with the substitution for references to torture of references to other forms of cruel, inhuman or degrading treatment or punishment.

2. The provisions of this Convention are without prejudice to the provisions of any other international instrument or national law which relates to extradition or expulsion.