If you are a pilot and convicted of a DUI, the good news is that such a conviction is "unlikely" to result in the loss of your ability to fly, but it will almost certainly make you unattractive to any of the large commercial carriers. Furthermore, undergoing something like an alcohol evaluation that will normally work to your advantage in the criminal case can cause you to be grounded because the outcome may cause you to fail your medical exam.
The FAA has a separate set of regulations and guidelines that requires pilots to present full disclosure, sometimes even before criminal charges are ever filed. This disclosure can and will work against you if not handled properly. While it is good to be familiar with the regulations, it is unwise to try to navigate the FAA on your own if your career depends on your ability to fly. You need representation for FAA purposes, as well as representation for the criminal and DoL procedures.
While there are very few qualified lawyers who handle both, a lawyer who focuses his/her practice to DUI defense should have a few aviation lawyers on their referral list. I certainly do.
Aviation law is an area where knowing a little can get you in a lot of trouble. A reputable lawyer will recognize this and such recognition is the hallmark of a lawyer who truly has your best legal and career interest in mind. While there are DUI/Aviation lawyers in the industry, they are so highly specialized they are few and far between. There is, however, a excellent selection of lawyers who are FAA specialist available. In fact, it is wise to hire a FAA specialist to work together with your DUI lawyer so that they may proceed in "lockstep" to defend and protect not only your Constitutional rights but also your career.
Over the years, I have worked with several pilots, and continue to do so, and each and every time I work with a FAA specialist. When I represent pilots who are charged with DUI I work with one of the most experienced and successful aviation lawyers in the state.