The defendant (D) may be convicted of unlawful and maliciouswounding contrary to s.20 of the Offences Against the Person Act1861.
Actus Reus - a break in the continuity of the whole skin, this is both outer and innerlayers of the skin (first two lawyers) usually with blood loss (Eisenhower)
Causation
Factual - 'butfor'test (RvWhite)
Legal - de minimis 'more than a minor cause' (R v Kimsey), operating and substantial cause 'most to blame' (R v Smith)
Novus Actus Interveniens - v's own actions (Roberts), v's self neglect (Wallace/Holland), actions of a 3rd party (Pagett), palpably wrong medical treatment (Jordan/Smith), thin skull rule (Blaue)
Mens Rea - intention or reckless to cause some harm albiet not serious (Mowatt)
Intention - aim, wish, desire to cause some harm albeit not serious (Mohan)
Recklessness - foresee a risk of causing some harmalbeit not serious and proceed to take it (Cunningham)