Scottish criminal and civil cases
In this essay, the legal maxim “he who asserts must prove" will be looked at to see to what extent this applies to Scottish criminal and civil cases. The general principle of who bears the burden of proof will be dealt with and the exceptions to the general principle. The standard of proof will also be looked at, as well as the three types of burden of proof - the legal burden, the evidential burden and the tactical burden.
In Scotland, the police investigate crimes with the view to making a report to the procurator fiscal who then decides what action is to be taken. In criminal trials, the burden of proof rests with the Crown, due to the presumption of innocence  . The case of Slater v HMA  demonstrated how the presumption of innocence is applied in Scots law the appeal court said “the jury was told that what is familiarly known as the presumption of innocence in criminal cases applied to the appellant with less effect than it would have applied to a man whose character was not open to suspicion. This amounted in our opinion to a clear misdirection in law. The presumption of innocence applies to every person charged with a criminal offence precisely the same way and it can only be overcome only by the evidence relevant to prove the crime of the commission of which he is charged"  . It is a general principal that the Crown bears the burden of proof, but in the following circumstances the burden passes to the accused. If the accused lodges a special defence of insanity or diminished responsibility,  it is for them to satisfy the burden of proof in relation to those matters by leading evidence from more than one source but they are not required to lead corroborated evidence  . The transfer of the burden of proof when a special defence is lodged comes from common law. In the case of Murray v HMA,  it was held that a failure to direct a jury that the requirement of corroboration did not apply to the defence was held to have led to a miscarriage of justice. Uncorroborated exculpatory evidence may prevent the Crown from satisfying the persuasive burden if it has raised a reasonable doubt in the mind of the court. The standard of proof the defence is required to meet for their special defence is the balance of probabilities opposed to the higher standard that the Crown must meet which is beyond a reasonable doubt. The evidential
Statute can also give rise to the transfer of the burden of proof from the Crown to the accused. The statute may deal with specific defences for example the Criminal law (Consolidation) (Scotland) Act 1995  . Says “any person who without lawful authority or reasonable excuse the proof whereof shall lie on him, has with him in any public place any offensive weapon shall be guilty of an offence"  . It is rare for statute to make express provisions as to who bears the burden of proof. It is normally a general provision in the statute as is seen in the Criminal Procedure (Scotland) Act  . Which says “where in relation to an offence created by or under an enactment any exceptions, exemptions, proviso, excuse, or qualification, is expressed to have effect whether by the same or any other enactment, the exception, exemption, proviso, excuse qualification need not be specified or negative in the indictment or complaint and the prosecution is not required to prove it but the accused may do so"  . When the burden is transferred to the accused, it is normally a persuasive one there is a very thin line as to ensure that this is not contrary to the presumption of innocence as guaranteed by the European convention on Human Rights.  Where a statute places a requirement on the accused to prove something but placing a persuasive burden on them would be incompatible with the convention rights, the statutory language can be read as imposing only an evidential burden 
The evidential burden is defined as follows that the party that has the evidential burden find sufficient evidence to demonstrate to the court that the issue is a live one that the court should consider it  . The crown normally bears the evidential burden however; the accused may also bear the evidential burden in relation to certain defences as has been already discussed. The provisional burden where the Crown has lead a case with sufficiently strong evidence it may be necessary for the accused to lead evidence to the contrary to avoid losing the case  ,but the burden of proof does not shift to the accused as was seen in the case of Tallis v HMA  . The appeal court disagreed with the trial judge’s direction to the jury, which gave the impression that the burden of proof did shift to the accused. The appeal court said, “The sheriff severed the last link in the impartiality required of him by giving the jury a serious misdirection in law. The gravity of this misdirection lies in plain indication to the jury that in certain circumstances the onus of proof shifts to the accused"  .
In the circumstances, that the accused is found in recent possession of stolen goods. This places a provisional burden on them to prove that they are not guilty. The case of Fox v Paterson  deal with the doctrine of recent possession as follows “if the rule is to have full effect in shifting the onus from the prosecution to the accused and raising a presumption of guilt which the accused must reargue or fail there conditions must concur (a) that the stolen goods should be found in the possession of the accused; (b) that the interval between the theft of the goods and their discovery in the accused possession be short and (c) that there should be other criminative circumstances over and above the bare facts of possession"  . If these three criteria are satisfied, the burden of proof is shifted to the accused to prove they did not steal the good or are not guilty of reset.
The standard of proof for criminal trials is beyond a reasonable doubt. The courts are very reluctant to put a figure as to what reasonable doubt is for example 70/30. The case of Buchanan v HMA  the appeal court said. “The trial judge was wrong to define reasonable doubt as the kind of doubt that would dissuade you from getting married or buying a house"  . In the case of A v HMA  the appeal court said, “A trial judge or sheriff adequately fulfils his duty if he tells the jury clearly and concisely. That the standard of proof that the crown is required to meet is beyond a reasonable doubt as one would cause a juror to hesitate or pause before taking an important decision in his own affairs. There is no need in our opinion for the trial judge to go beyond those directions" 
In civil cases in Scotland, the burden of proof rests with “the party who would fail if no evidence were adduced on either side"  . On the other hand, “he who asserts a right a right given to him by the law must prove the facts necessary to establish it"  . The two quotes above are illustrating the burden of proof rest with the pursuer. .
Depending on the action being raised, if it is one of delict based on negligence it is for the pursuer to lead evidence to prove this, if the defender wishes to raise a defence such as contributory negligence or volenti non fit injuria ei qui affirmat non ei qui negat, incumbit probatio  (on he who asserts, not he who denies is the obligation to prove). An area of civil law where the burden of proof can be transferred from the pursuer to the defender is contract law. For example if one party loans money to another party and it is disputed that it was a loan the burden of proof shifts to the party claiming it was a gift as there is a rebuttable presumption against gifts under Scots Law. To prove that it was a gift and not for some other purpose.
There are circumstances where statute can alter who bear the burden of proof. The case of Nimmo v Alexander Cowan & Sons Ltd  is one such case where the burden of proof was transferred to the defender under the Factories Act 1961  . The defender admitted he failed in his statutory duty to “take so far as reasonably practicable be made and kept safe for any person working there"  . It was held “that it was for the pursuer to prove that the premises were not safe but not that it was not “reasonably practicable" to be made safe. If the defender wished to rely upon this proviso he bore the burden of proof in that respect"  . Lord Wilberforce said “exceptions etc. Are to be set up by those who rely on them"  .
The standard of proof in a civil case is on the balance of probabilities. There have been cases that have argued that if the case involves criminal conduct the standard of proof should be raised to the standard of a criminal trial beyond a reasonable doubt. One such case to put this argument forward was Mullan v Anderson  where a full bench decided the following “even though the civil under consideration involved an allegation of murder there was no reason to depart from the normal rule of proof beyond a reasonable doubt. There is an exception to the rule that the standard of proof in civil cases is balance of probabilities it comes from statute. The Children’s (Scotland) Act 1995 says where an application is made to a sheriff to establish grounds of referral to a children’s hearing  that the child has committed a criminal offence then the standard of proof required in criminal cases shall be required.
In conclusion, the legal maxim “he who asserts must prove", does apply to Scottish civil and criminal cases. There are numerous exceptions to this rule but never the less it remains the case for the Crown in criminal cases to prove their case beyond a reasonable doubt by leading their evidence this is due to the sanctions that can be imposed in criminal trials, which can include the loss of liberty. This is also seen in civil cases where it is for the pursuer to prove their case on the balance of probabilities as the consequence of the case going against the defender result in a decree against them but no as in criminal case the loss of liberty.