It’s a frightening moment: you’re driving home from dinner and drinks when suddenly you see flashing lights and hear a siren behind you. Even under the best of circumstances, an encounter with law enforcement can be nerve-wracking. What should you do when you’re pulled over after having a few drinks? Here are a few things you should know as articulated by a DUI and DWI lawyer Phoenix trusts:

1. You Don’t Have to Answer (Most) Questions

As with any encounter with law enforcement, you have the right under the Fifth Amendment of the U.S. Constitution to remain silent and refuse to answer potentially incriminating questions. This means that you don’t have to tell a police officer how many drinks you’ve had or where you’re coming from. However, in many states, you are required to comply with lawful orders or requests from law enforcement officers. Often, this requires you to comply with a request to identify yourself with your driver’s license and provide the officer with registration and liability insurance information upon request. Similarly, if an officer requests that you step out of your vehicle, you are required to comply.

2. You Don’t Have to Perform Any “Tests” or Give a Sample Voluntarily

If you’ve been stopped after drinking, you may be asked by the officer to perform some tests. Commonly, the officer will add that he just wants to make sure that you’re okay to drive home. Whether or not that’s actually true, these tests are also the next step of a standard DUI/DWI investigation, and a video of your performance is almost always a central piece of evidence in a DUI/DWI prosecution. It’s important to know that you are not required to perform these tests. Given that some people have trouble performing the tests when completely sober, you should decline to perform them if asked.

The same principle applies to a request for a breath or blood sample. If you’re worried about what the result might be, it is usually best to refuse. The officer can get a warrant to draw a blood sample, but officers don’t always follow through with the paperwork and hassle it takes to get the warrant. Even if they do apply for a warrant, the warrant—and thus the test result—may be subject to exclusion in your case if the officer doesn’t do the process correctly.

3. Know Your Rights, But Be Polite

As important as it is to know your rights, you should also exercise them intelligently and with respect. Know that your interaction with law enforcement is being recorded from start to finish. Even if the officers don’t get video of you doing the tests or get a sample to test, people who act belligerent or disrespectful aren’t likely to get any favors from officers, prosecutors, or jurors. Additionally, emotional volatility and poor decision-making are classic signs of intoxication that can be used against you. Refuse to aid law enforcement’s investigation, but do so calmly and respectfully.