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IR35 case law


Case law is used to determine the IR35 status of a contractor as either employed (inside IR35) or self-employed (outside IR35).

This article explains what case law is, and provides some guidance for finding further more detail information about specific cases.

What is Case Law?

Definitions from Duhaime:

If a rule of law cannot be found in written laws, lawyers will often say that it is a rule to be found in "case law". In other words, the rule is not in the statute books but can be found as a principle of law established by a judge in some recorded case.

A basic principle of the law applies whereby, once a decision (a precedent) on a certain set of facts has been made, the courts will apply that decision in cases which subsequently come before it embodying the same set of facts. A precedent is binding and must be followed.

HMRC, IR35 and case law

From the HMRC leaflet IR56:

“The law for tax and social security legislation does not define ‘employment’ and ‘self- employment’. But, over the years, the Courts have considered this issue and their guidance on whether an individual is an employee or self-employed is known as case law.”

How should a contractor use case law?

A contractor would not be wise to try and learn all the IR35 case law, and employment law, with a view to ‘doing it on their own’.

Firstly, this would be a huge task costing a great deal of time and is best left in the hands of professional lawyers.

Secondly, as a novice ‘lawyer’, trying to combat status disputes with HMRC significantly reduces your chance of success.

However, what is useful is for a contractor to have a good overview of the process of mitigating the IR35 risk, and knowing when to get professional help.

The following articles are recommended reading:

Case law applicable to IR35

This section is more applicable for those wishing to dive into the detail of the case law.


They have published the case law section of their employment status manual on their site.

ESM7000 – Case Law

Bear in mind that not all these cases are directly applicable to IR35.


Overview of background case law, including:

  • Express & Echo Publications v Tanton [1999]
  • Carmichael v National Power Plc [1999]
  • Smith & Chanton Group v Costain Ltd [1999]
  • Chen Yuen v Royal Hong Kong Golf Club [1998]
  • McManus v Griffiths [1997]
  • Hall (Inspector of Taxes) v Lorimer [1994]
  • McMenamin v Diggles [1991]
  • O'Kelly v Trusthouse Forte Plc. [1983]
  • Swan Hellenic Ltd v Secretary of State [1983]
  • Massey v Crown Life Insurance Co. [1978]
  • Ready Mixed Concrete Ltd v. Minister of Pensions & NI [1968]
  • Market Investigations Ltd v Minister of Social Security [1968]

Detail for IR35 Cases, including:

  • Synaptek v Young (2003)
  • LIME IT v Justin (2002)
  • FS Consulting v McCaul (2001)
  • Battersby v Campbell (2001)

Published: 20 December 2006

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