Realistically, if a collection attorney is contacting you, the only way to keep them from suing is to come to some sort of settlement agreement. However, if you are sure the debt isn't yours, the debt is more than 6 years old, or there is some other reason you can prove you don't owe the debt, you may be able to preempt a collection suit by asserting a fair debt collection claim. Any time you are first contacted by a debt collector or collection attorney, be sure to assert your rights to validate the debt.
Filling out the asset form won't help, it's primarily used to see what assets you have that can be seized or garnished to pay the debt, and even if it showed you didn't have any collectable assets, they will likely still file suit in order to preserve the debt through judgment.
If you own a home, you should file for homestead protection. As for your other assets, exemption laws automatically protects them. The burden is on the creditor to show you have non-exempt assets.
Hope this answers your questions, good luck to you.
Getting sued by them isn't the worst thing in the world. If they are a third party debt collector (debt buyer) they often can't prove that they own or that you owe the debt. The filing fees all have to be paid by them and the burden of proof falls on them. I don't know the rules in MA (although I am originally from there), but in my jurisdiction you do not have to pay court costs to defend a suit. If you are able to where you live, try contacting a local legal aid if you end up getting sued to try to qualify for free legal help.
Best of luck and Go Sox!
I agree with my colleagues who have answered your question.
I would add filing bankruptcy can stop a creditor from suing you, at least for a period of time. When a person files bankruptcy, all creditors have to immediately stop all collection actions. This is due to what is called the Automatic Stay. The Automatic Stay allows a person who is being hounded by creditors to have some room to think and make better decisions while they go through the bankruptcy process.
If this is a small debt and you don't have much more debt then bankruptcy is probably not the answer for you. Also, if you don't want to spend any money then you won't want to spend the $306.00 filing fee for a Chapter 7 bankruptcy or the $50.00 or so to take a credit counseling course before filing, not to mention attorney fees.
So, in short, the Automatic Stay can halt a creditor from suing you for a period of time. Whether bankruptcy is for you is another story. Here is a link to some information provided by the bankruptcy court.