Hi Ms. Carter,
Thank you for taking the time to participate and post in the community. I am sorry to hear about the funds hold you are experiencing. If you give us a call at 1-800-531-8277 a member service representative can explain why there was a hold placed on your deposit. This document (USAA's depository agreement, page29) details the average hold times for different types of deposit. Attached are some screen shots of the text.
The best defense against a deposit hold is to be prepared for it. They are basically a fact of life nowadays due to significant losses experienced by both banks and consumers from check fraud. It is always best to assume that any non-cash deposit will be held for at least 7 business days.
Remember that the funds are not actually in your account when you deposit a check until the money has been received from the other bank (normally 2 - 5 business days minimum). If the check is bad, it could be a few weeks before a bank is notified, at which time they will remove it all from your account immediately. If you spent it, then your account will go in the negative, resulting in a debt and possibility of racking up NSF fees.
As Briana posted (which actually starts on page 18), bank hold policies are contained in each banks Depository Agreement, and the language is fairly standard for many of the banks You might benefit from Regulation CC if you deposit the check in person, but that still is no guarantee that a significant hold won't be placed (see delaying fund availability in the above link). This is usually explained in the "Longer Delays May Apply" section of the various Depository Agreements.
Another option is to take the check to the bank that issued it and cash it. If you don't have an account with them, they may charge you a fee, but you will not have any hold time.