First, you do have to respond to the Summons and Complaint, to avoid having a default judgment entered against you. That means filing an Answer, explaining that (1) They have named the wrong person in the Complaint, (2) You do not owe any debt, and (3) that the relevant statute of limitations
To respond to a Complaint, a person must admit or deny each of the allegations individually, or state that he lacks sufficient information to admit or deny the allegations. Because of the amount of time that has passed, you may not have enough information to answer any of the allegations. That's OK - you can just say as much. Here is a sample of what an Answer might look like.
The statute of limitations is a complete defense to a lawsuit. In Arizona, the statute of limitations for breach of contract
is six years from the date that the debt was incurred, or that a payment was made by the borrower. If you have had no communication about the debt since 1991, it is far too late to collect from you now.
Also, if the Complaint does not provide sufficient information for you to even figure out what the debt is, you can file a Motion for a More Definite Statement, asking for information regarding the debt, or a Motion to Dismiss
for Failure to State a Claim, asking that the judge simply enter judgment in your favor. Just keep in mind that the judge can always order them to amend the Complaint to be more specific.
You may also want to check your divorce decree, to see if this particular debt is mentioned, and if it made you or your ex responsible. A court retains the ability to enforce a divorce decree, so you may be able to bring your ex in as a party, if his name was on the account, or get a judgment against him if you wind up being required to pay anything (which seems unlikely).
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