A power of sale not the same of a judicial sale when your home ends up on the foreclosure list. This is very similar to the process though. When you fail to make a payment on your property the mortgage lender is going to have your served with papers. These papers will demand payment of the loan. There will be a waiting period they have to give you in order to come up with the money. When this time goes by and they have not received payment they will draw up a deed of trust. The deed of trust is a document that will transfer the trust of the property from the lender to a trustee to handle the foreclosure process.
When the property on a foreclosure list makes it to a trustee in a power of sale the trustee is going to try to sell the home at a public auction for the lender. This is easier for many banks that don't have the time to go through the auctions themselves or have the staff. They hire a professional trustee to do the work for them.
In most cases, when a lender uses a trustee for a power of sale the foreclosure list has to go through a judicial review process. This is a way for the courts to know that this process is entirely legal and carried out properly. The lender will be required to post a public notification that the home is on the foreclosure list and going up for sale at an auction.