Detailed Answer: How to protect yourself when signing a witness affidavit in a Wisconsin car-accident case

If someone asks you to sign an affidavit about a car accident in Wisconsin, you should take several clear steps to protect yourself legally. An affidavit is a written statement sworn to be true and can be used in court. Signing an affidavit that is false or that you do not understand can expose you to serious legal risk. Under Wisconsin law, knowingly making false statements under oath can be criminally punished. See Wis. Stat. § 946.31: Perjury.

1. Understand what an affidavit is and how it can be used

An affidavit is a written statement of facts you swear (or affirm) are true. Affidavits are commonly used in civil cases to support motions (for example, summary judgment) and to preserve witness statements. In Wisconsin civil practice, affidavits are frequently submitted under statutes and court rules that govern evidence and motions; for example, affidavits often support or oppose summary judgment motions. See Wis. Stat. § 802.08 for Wisconsin summary judgment procedure: 802.08. Because an affidavit is sworn, false statements can lead to criminal charges for perjury.

2. Before you sign: read, correct, and limit

• Read every line. Do not sign anything you have not read in full.
• Make corrections in writing. If a statement is wrong, cross it out (or request a corrected draft) and write the accurate fact. Initial or otherwise mark changes so there is no ambiguity.
• Stick to first-hand facts. Only include what you personally observed. Avoid speculation, guesses, or repeating what others told you unless you clearly identify the source (and whether it is hearsay).
• Be specific about time, place, weather, vehicle descriptions, directions, speeds (if you actually estimated), and what you physically saw or heard.
• Do not sign blank or incomplete forms. If the affidavit is incomplete, ask the preparer to finish it before you sign.

3. Swearing, notarization, and formalities

An affidavit is usually sworn before an authorized official (for example, a notary public or other official who can administer oaths). Confirm who will administer the oath and that the document will include the proper jurat (the part that shows you were sworn). Ask for a copy of the signed and notarized affidavit for your records.

4. Be mindful of criminal exposure — perjury

Knowingly making false statements under oath may be a crime under Wisconsin law. See Wis. Stat. § 946.31: Perjury. If you are unsure whether a statement is true, do not affirm it. Instead, say you do not recall, or provide a statement such as “to the best of my knowledge” or clearly identify what is a belief versus a directly observed fact. If you believe a question could force you to incriminate yourself, you may have rights to decline to answer; consider speaking with an attorney before signing.

5. Ask how the affidavit will be used and who wrote it

Find out whether the affidavit was prepared by a lawyer, an insurance company, or another party. Ask whether the affidavit will be filed in court, used only for an investigation, or shared with insurers. Knowing the intended use helps you tailor your statement to facts only and helps you decide whether to consult a lawyer first.

6. Get a copy and preserve evidence

• After signing, get a full copy of the affidavit (the final version with the notary jurat or signature block) and keep it in your records.
• Keep any photographs, notes, or contact details you used to prepare your statement. If your memory changes, note the date and reason for the change; do not sign a new affidavit that contradicts your earlier sworn statement without legal advice.

7. Know your rights about subpoenas, testimony, and self-incrimination

Signing an affidavit does not waive all rights. If you are later subpoenaed to testify, you must appear if properly served. If testimony could incriminate you, you may have a right to decline to answer based on the privilege against self-incrimination. If you have any risk of criminal exposure, consult a lawyer before making sworn statements.

8. When to get legal help

If you are unsure about any statement, are worried you might be accused of lying, or believe the affidavit could expose you to criminal or civil liability, contact a lawyer. A lawyer can review the proposed affidavit, suggest precise wording that accurately reflects your memory, and advise you about whether to sign. If you cannot afford counsel, consider local legal aid or a public defender if criminal exposure is possible.

Quick checklist before signing an affidavit

1. I have read the entire document.
2. All factual statements reflect my firsthand observations.
3. I corrected any inaccuracies and initialed changes.
4. I understand the document will be sworn and may be used in court.
5. I received a complete, signed, and notarized copy for my records.
6. I contacted an attorney if I had any concerns.

Helpful Hints

• Write down what you remember as soon as possible after the accident. Date and store those notes. Fresh notes help you prepare an accurate affidavit.
• Photographs, video, and contact information for involved parties and witnesses strengthen your factual account.
• Avoid legal conclusions in your affidavit (for example, “the driver was negligent”). Stick to observable facts (for example, “the driver ran the red light and struck the passenger side of the other car”).
• Do not sign if someone asks you to add statements you did not observe. If pressured, decline and ask for time to consider or to speak with counsel.
• Keep copies of all communications about the affidavit, including emails and messages asking you to sign.
• If a notary is not available immediately, do not sign and later claim you signed under a notary’s supervision. Wait for proper administration of the oath.

Resources

Wisconsin statute on perjury: https://docs.legis.wisconsin.gov/statutes/statutes/946/31

Wisconsin summary judgment procedure (common context where affidavits are used): https://docs.legis.wisconsin.gov/statutes/statutes/802/08

Disclaimer

This article is informational only and does not provide legal advice. It is not a substitute for speaking with a licensed lawyer about your specific situation. If you have concerns about signing an affidavit or your possible legal exposure, contact a Wisconsin-licensed attorney.