Drunk driving is a serious criminal charge, even when nothing else happens before you get stopped. If you are involved in an accident and are found to be intoxicated, you are likely going to face more serious charges. There are several things that happen when you are involved in a wreck when you've been drinking and driving.
The police officer who shows up at the scene of the crash is going to be paying attention to various things. If they think that you are impaired at all, they will try to determine if this is the case. You might be asked to take a breath test at the scene. The officer may tell you to take a field sobriety test.
In some cases, you might be taken for a blood or urine test. These are done to determine your blood alcohol concentration (BAC). Even if you don't appear intoxicated, you might still be required to take these tests if there is a death or a serious injury caused by the accident.
If your BAC is at or above the legal limit, you will face charges for drunk driving. You may also face other criminal charges based on the severity of the accident and the results of it. For example, you may face a manslaughter charge if someone is killed in the wreck.
On top of the criminal charges, there is a chance that you will be named as the defendant in a civil lawsuit. This comes from the victims of the crash who are trying to seek compensation for the damages in the crash.