Voluntary Intoxication

• D has voluntarily consumed alcohol or drugs commonly known to make people aggressive or out of control.

  If they're incapable of forming the necessary mens rea, the D will have a defence to specific but not basic intent crimes.
• If there is voluntary intoxication, but the D had not formed intent, then they're not guilty of a specific intent crime. (DPP v Beard)

  True test is whether the D had infact formed the necessary mens rea. (R v Sheehan and Moore) Voluntary intoxication such as by drugs or alcohol is no defence to crimes requiring only basic intent. (DPP v Majewski) Where the D is suffering from a mental disorder brought on by past voluntary intoxication, he can use the defence. (R v Harris)
• Specific intent crimes:

  Mens rea is intention only. Intoxication finds the D not guilty of crimes of specific intent.
• Basic intent crimes:

  The mens rea is either intention or recklessness. If the D is voluntarily intoxicated, he will not have a defence to a crime of basic intent if he has been reckless. Involuntary intoxication will provide a defence to all crimes.
• Specific intent crimes required mens rea to include thinking as to consequence or purpose, whereas basic intent crimes simply require mens rea as to the actus reus: not the consequences. (R v Heard)
• If the prosecution can't charge someone for a specific intent offence, they will use an appropriate corresponding drop down basic intent offence/crime.

  An intoxicated defendant will not automatically be found guilty of a basic intent crime simply by committing the actus reus of the offence.
• The test to see whether a D is reckless is what the D's themselves would have foreseen had they not been drinking. This is a different approach that asks the jury to consider whether the D would have realised the risk in question had he not been intoxicated. (R v Richardson and Irwin)
• Dutch Courage:

  If someone deliberately gets intoxicated to give themselves Dutch Courage to commit a crime, his intoxication will not be a defence to any crime, even to crimes that can only be committed with a specific intention.

  D had formed mens rea at the relevant time. (A.G for Northern Ireland v Gallagher)
• Intoxication and Self-Defence:

  There is no defence if the D has made a mistake as to the need for self-defence due to intoxication. (Criminal Justice and Immigration Act 2008 s.76(5)) and the case of R v O'Grady