The phrase "testamentary freedom", i.e. the freedom to leave your property to whomever you wish in your Will, is well known in England and Wales, but what can you do if you have been written out of a will or want to challenge the wishes of a recently departed family member?

It is surprisingly common for individuals to try to disinherit their families and leave it all to the proverbial cats' home. The more unusual cases make the papers – remember of the case of Golda Bechal, an 88-year-old widow, whose relatives challenged her will after she left most of her £10m fortune to the owners of her favourite Chinese restaurant – but for most the stress and the distress will remain within the family circle.

As people are now living longer many often decide to change their Wills later in life without the assistance of a solicitor. This can lead to family members suspecting foul play if they have been written out of the Will. Challenges to Wills are costly and difficult to win, not least because the principal party one might want to obtain evidence from is no longer with us...! The Courts will nonetheless look at all of the facts of the case and a great deal may depend on how the witnesses involved come across in Court.

So, if you discover that you have been "written out of" a Will in favour of your local takeaway or the cats' home, can you actually do anything about it?

Legally-speaking, it is possible to challenge a Will for one or more of the following reasons:

• Lack of proper formalities
• Lack of testamentary capacity
• Lack of knowledge and approval
• Undue influence and fraud

Lack of proper formalities

A Will must be made in writing and signed by the testator (or in his presence and at his direction) in the presence of two witnesses who must each also attest and sign the Will in the presence of the testator. If any of these requirements are missing the Will is invalid.

Lack of testamentary capacity

To make a valid Will the testator must have the requisite mental capacity. The testator must be capable of understanding that he or she is making a Will and disposing of their assets on death. The testator must also be capable of understanding the extent of his estate and appreciate the claims on that estate to which he ought to give effect.

The difficulty with proving this ground is that you must produce evidence of the testator's capacity after their death. When a Will is drawn up by a solicitor and if there are doubts about a person's capacity, the solicitor should ask a doctor to assess capacity before a Will is made. The first step after death therefore should be to get the solicitor's Will file to check whether this occurred. Obtaining the file / surrounding documentation is easier than it sounds because the usual rules of confidentiality do not apply in these circumstances. It will also be necessary to get copies of the deceased's medical records, any hospital records and information in relation to any drugs the deceased was taking. It is possible to ask a specialist to review the medical records to try to help determine whether the deceased had capacity at the time the Will was made (if a doctor was not involved at the time).

Lack of knowledge and approval

A testator must know and approve the contents of the Will. If a Will has been properly executed, it is presumed that the Will is valid on this ground and, generally-speaking, you will have to prove (on the balance of probabilities) that the testator did not know and approve the contents of the Will. However, if the circumstances surrounding the preparation of the Will are such to "excite the suspicion of the Court" (i.e. they are unusual for some substantive reason), the burden of proof can pass to the person seeking to rely on the Will.

Circumstances which might excite the suspicion of the Court could include the main beneficiary preparing the Will for the testator – for example, a carer preparing a will on behalf of an elderly or infirm patient.

Undue influence and fraud

Undue influence means coercion, but no physical force is necessary. This is not the same as persuasion. Reminding the testator of their family obligations or what you have done for them in the past is not undue influence. In addition, there is no presumption of undue influence in the context of Wills, so demonstrating that there was a close relationship between the parties will not be sufficient. It is essentially down to the person alleging undue influence to show that the testator was coerced into making the Will. Given that the testator is no longer around and that they have often been isolated by the person against whom undue influence is alleged, it is one of the most difficult allegations to sustain - there may be lots of suspicion, but relatively little hard evidence!

What to do if you suspect the Will is invalid

If you suspect a Will is invalid on one of the above grounds you should consult a solicitor as soon as possible. The solicitor will start investigating the circumstances surrounding the preparation of

the Will and will probably enter a 'caveat' with the Probate Registry to prevent a grant of probate being taken out in the meantime. It is important to act as quickly as possible to prevent the estate being administered in accordance with an invalid Will and to prevent the dissipation of assets.

What happens if the challenge is successful?

The Court cannot just decide how the estate should be distributed. Any prior valid Will will be admitted to probate in place of the invalid one. If there are no previous Wills, the intestacy rules will apply to the estate. It is clearly important to consider whether you will benefit under any previous Will or intestacy before embarking on legal proceedings to challenge the Will.

Lastly, it is crucial to remember that commencing legal proceedings can be a risky and expensive process. If you do so unreasonably and lose, the chances are you will have to pay a good percentage of the winning party's costs from your own pocket, in addition to your own costs.

Kellie Jones is a solicitor at Boodle Hatfield. She can be reached via email: kjones@boodlehatfield.com