Motion to Avoid Lien
Although removing or avoiding a lien doesn't happen automatically as part of your Chapter 7 proceedings, it's relatively easy to accomplish if you have not received a discharge yet. You can file a request with the bankruptcy court called a motion to avoid lien. You must serve a copy of the motion on all interested parties. These include the trustee and the creditor who perfected or created the lien by filing a copy of its judgment with the proper government office. The creditor can object by filing a response to your motion, but it probably won't do so if the associated debt is clearly dischargeable.
Conditions of Avoidance
When you filed your bankruptcy petition, you should have submitted a statement of intention as part of the documentation. This form tells the court what you intend to do with any property that's secured by loans or has other liens against it. The statement includes a box you can check off for each piece of property, indicating that you've claimed it as exempt from the bankruptcy proceedings. This protects its equity so the trustee cannot liquidate the property to pay your creditors. Hopefully, you checked this box off. Otherwise, you must amend your bankruptcy petition to do so before you can proceed with avoiding the lien. This may require an extra motion, seeking permission from the court to do so. Successfully avoiding the lien requires that there is no equity in your property after accounting for the mortgage lien and your homestead exemption. There's no value available to the creditor to satisfy the underlying debt.
Chapter 13 Bankruptcies
If you filed for Chapter 13 rather than Chapter 7, avoiding a lien also requires a motion. The process is similar; you must establish to the court's satisfaction that the value of the property is not sufficient to cover all encumbrances against it. This can include consensual liens, such as those created by a second mortgage or home equity loan. If your property is underwater – its fair market value is less than the first mortgage against it – a successful motion "strips off" junior lienholders. Their associated liens are removed and these become unsecured debts.
If you've already received your Chapter 7 discharge, it's not too late to avoid a lien. You must reopen your bankruptcy first, however. Doing so doesn't affect your discharge – you're still absolved from responsibility for paying your eliminated debts. You must first file a motion asking the court to reopen your proceedings, and then you file a second motion to avoid the lien. You must meet all the same conditions that would have applied had you filed the motion before your discharge.