If you think someone is likely to go to court and challenge your durable power of attorney or claim that you were coerced into signing it, you can take several steps to head off problems.

Go to see an estate planning or elder law attorney to discuss your concerns. You may want the lawyer to review the estate planning documents you've created yourself, or to draw up some documents for you. An experienced estate planning attorney can answer questions about your durable power of attorney and about your other estate planning documents as well. For example, you may also be expecting challenges to your will, a trust or healthcare wishes. You can talk with a lawyer about all of these issues. The point is to have the lawyer put your fears to rest by answering your questions and confirming that your estate plan will hold up under the challenges of your stubborn relatives. Your attorney can also testify about your mental competency, should the need arise.

Sign Your Document in Front of Witnesses. You can sign your document in front of witnesses, even if your state does not require it. After watching you sign, the witnesses themselves sign a statement that you appeared to know what you were signing and that you did so voluntarily. If someone later challenges your competency, these statements will be strong evidence that you were of sound mind at the time you signed your document.

Get a Doctor's Statement. You may also want to get a doctor's statement around the time you sign your durable power of attorney. The doctor should write, date and sign a short statement saying that he or she has seen you recently and believes you to be of sound mind. You can attach this statement to your power of attorney document. Then, if necessary, your attorney-in-fact can produce the statement as proof that you were of sound mind when you signed your power of attorney.

Make a Videotape. You can also videotape a statement of your intent to make and sign the durable power of attorney. Such a step should not be necessary, but going to this length may further minimize the chances of a successful challenge to your competency. Be warned, however, that using a videotape may work against you. The person challenging your power of attorney document will want to use any visible quirks of behavior or language as evidence that you were not in fact competent when you made your document. If you do make a videotape, keep this tape with your power of attorney document.