The BON does their own investigation into the matter and will make the decision of what to do regarding your license and whether they feel you have a problem with alcohol and/or drugs. They may refer you to have an evaluation done at a place of their choosing which will help them decide whether its safe for you to continue working as a nurse, or they may put restrictions in place.
You may be placed in a Nurses Assistance Program to monitor you for however long they deem necessary!
Bottom line, if you got a ticket for driving under the influence because you failed a breathalyzer test or any other test the police official may have conducted on you...you are guilty! I don't know how having an attorney in this case will be of any help!
The BON does a thorough investigation into such matters and will speak with all people relevant to the case...meaning employers, police officials, coworkers, doctors, counselors, etc.