In my attorney-client contract, I specify a specific period of time that I will retain a client's file. After that period of time, the client agrees that I can destroy their file.
At the end of a case, I return all original documents to a client. In fact, I try never to keep any original documents (such as tax returns, pay stubs, etc.) whenever possible even during an active case in case my office were to be damaged by fire or flood.
Many attorneys these days scan files and physically destroy their client files due to the cost of storage of client files.
In many cases, you can go to the district clerk in the county where you case was filed and order a certified copy of your file and get a copy of the entire case file. You don't ever need to contact your attorney. The cost to get a copy of your court file is minimal.
You can also contact the State Bar of Texas in Austin or go on line and visit their website and see if they can answer you question. With scanning becoming so popular the policies on physically retaining client files have been changing in recent years.