Standards of proof

Standards of proof compared across courts and other bodies

Q: Does a more serious allegation need more proof in civil cases?

In the UK there is only one civil standard. Australian courts must take the gravity of the allegation into account in applying it.

Q: What standard do MPs face in a standards inquiry?

The House of Commons uses the balance of probabilities.

Last checked 6 November 2026 · 8 sources

Short answer

The standard of proof is how sure a decision maker must be before it finds an allegation proved. Criminal courts need proof beyond a reasonable doubt in the United States ¹, and in England and Wales the court must be sure ². Civil courts in the UK use one standard, more probable than not ³. Australia's federal Evidence Act sets the balance of probabilities ⁴. Some US claims need clear and convincing evidence ⁵. The UK House of Commons standards system uses the balance of probabilities ⁶.

US criminal: Proof beyond a reasonable doubt of every fact needed for the crime ¹
UK civil: Only one civil standard, the fact in issue more probably occurred than not ³
Australia civil: Balance of probabilities, with the gravity of the allegations taken into account ⁴
US intermediate: Clear and convincing evidence, highly probable ⁵
UK Commons standards cases: Balance of probabilities ⁶

Criminal standard: beyond reasonable doubt

In In re Winship, decided on 31 March 1970, the US Supreme Court held that the Due Process Clause protects the accused against conviction except on proof beyond a reasonable doubt of every fact needed to make out the crime ¹. The case applied the rule to juvenile proceedings for conduct that would be a crime for an adult ¹.

In England and Wales, the Code for Crown Prosecutors notes that a court may convict only if it is sure of guilt ². In the European Union, the burden of proof is on the prosecution and any doubt about guilt benefits the accused ⁷.

Civil standard: balance of probabilities

In In Re B (Children) in 2008, Lord Hoffmann said the time had come to say once and for all that there is only one civil standard of proof, proof that the fact in issue more probably occurred than not ³.

Australia sets the civil standard for federal courts in the Evidence Act 1995 (Cth). A party's case is proved on the balance of probabilities ⁴. In deciding, the court must take into account the nature of the cause of action or defence, the nature of the subject matter, and the gravity of the matters alleged ⁴.

Intermediate test: clear and convincing evidence

Some United States claims sit between the civil and criminal standards. The Legal Information Institute describes clear and convincing evidence as a burden between preponderance of the evidence and beyond a reasonable doubt ⁵. In Colorado v. New Mexico in 1984 the Supreme Court said the evidence must make the claim highly probable ⁵. States differ on where it applies, but fraud and wills claims often need it ⁵.

Tests before a finding: charging and investigation thresholds

Prosecutors apply their own tests before a case reaches court. These are not standards of proof for guilt. The CPS evidential test asks if there is a realistic prospect of conviction, meaning a court is more likely than not to convict ². The CPS Threshold Test, for limited cases, starts from reasonable grounds to suspect ². The US Justice Manual asks if the admissible evidence will probably be sufficient to obtain and sustain a conviction ⁸.

Disciplinary and standards bodies use civil-style tests. The House of Commons Procedural Protocol says an allegation is proved if it is more likely than not to have happened, the balance of probabilities ⁶. The Commissioner opens an investigation only if there is sufficient evidence to justify one ⁶.

Side-by-side table

Test	Where it is used	What it means
Beyond a reasonable doubt	US criminal trials ¹	Proof of every fact needed for the crime ¹
Sure of guilt	Criminal courts in England and Wales ²	The court may convict only if sure ²
Balance of probabilities	UK civil cases ³, Australian federal civil cases ⁴	More probable than not ³
Clear and convincing	Some US civil claims ⁵	Highly probable ⁵
Realistic prospect of conviction	CPS charging decisions ²	A court is more likely than not to convict ²
Balance of probabilities	UK Commons standards cases ⁶	More likely than not to have happened ⁶

Common questions

Is balance of probabilities the same as 51 percent?

The UK test is whether the fact more probably occurred than not ³. The sources read do not use a percentage.

Does a more serious allegation need more proof in civil cases?

In the UK there is only one civil standard ³. Australian courts must take the gravity of the allegation into account in applying it ⁴.

What standard does a prosecutor use to charge?

In England and Wales, a realistic prospect of conviction and the public interest ². In US federal cases, evidence that will probably be sufficient to convict ⁸.

What standard do MPs face in a standards inquiry?

The House of Commons uses the balance of probabilities ⁶.

Rules and charges change. Check the official source linked on this page before you pay or travel. Spotted an error? Email hello@allegationindex.org.

Sources

Allegation, charge and finding: three different stages
An allegation is a claim, a charge is a formal accusation by a prosecutor, and a finding is a decision by a court or tribunal. How each stage works in law.
What an allegation status means in official processes
How courts, regulators and standards bodies label an allegation at each stage, from complaint and investigation to notice, charge, finding and appeal.
How parliaments handle complaints about members
How the UK, Canada, the US House and Malta take, investigate and decide complaints about legislators, with tests, outcomes and appeals.
Upheld, not upheld, withdrawn and dismissed explained
What it means when a complaint is upheld or not upheld, when a charge is withdrawn or discontinued, and when a case is closed with no action.