For years, one of the top pieces of conventional wisdom flowing out of criminal defense offices has been the idea that people suspected of driving under the influence of alcohol should refuse to take a breathalyzer test. The logic behind this advice seems sound on its face, but it’s no longer relevant with the approaches taken by police officers in many states. This aging logic suggested that if a person refused the breath test, the officer would have to spend hours getting a warrant to conduct a blood test. In many cases, the logic held, the officer wouldn’t do this, and without a blood or breath test, the state could struggle to prove its case. That might have been true then, but it’s not true now. Here’s why this advice is outdated and dangerous.

Blood tests generally are regarded by judges and juries to be more reliable than breathalyzer tests.

Jurisdictions can obtain warrants and conduct blood tests quickly

In many jurisdictions, the standard operating procedure is to get a warrant electronically and have the blood test done right away. In some cases, these police departments and sheriff’s offices have roving medical stations to handle testing on-site. If you choose to refuse a breath test, you are likely to have your blood drawn a few minutes later. No longer is a refusal to take a breath test a path toward zero evidence.

Blood tests can detect prescription and illicit drugs

If you’ve been using any drugs at all, the blood test may detect these drugs, giving the prosecution another route through which they can pursue a conviction for DUI. Even if you are just using your prescription drugs, they may argue that you were not authorized to operate a car while using the drug. A breath test will reveal only alcohol, so you’ll be protected from the potential for more a complicated DUI case if it happens to go to court.

The scientific reliability of blood tests over breath tests

Much of the fear over breath tests has revolved around the unreliability over those tests. While many are scared that the test will give a false reading, they should think about what happens at the next step in their criminal process. If you end up in a trial, it will be tough for your lawyer to dispute a blood test. Many skilled attorneys can convince jury members to disregard breath tests because of issues of reliability. Jurors tend to believe the science behind blood tests, though. If there’s a choice between the two, you’d much rather be trying to deflect from a breathalyzer result than a blood test result.

The consequences of refusal

Jurisdictions have become wise to the tricks of drivers today. They know that many people refuse a breath test to avoid detection and prosecution. In response, states have used their administrative power to take away the driving privileges of individuals who refuse to take a breath test. You could lose your license for a year if you refuse, which is a stiff penalty for a first-offense DUI. As these consequences grow worse, it makes little sense to take them on when you’re going to face a blood draw anyway.

Keeping all your options open

Many people will try to avoid maximum consequences for a first offense by taking a pre-trial diversion program. Across the country, pretrial diversion programs are designed to keep people from having to go to trial or jail if they have never been convicted of a crime before. In many jurisdictions, including some in Texas and California, it is the policy of the district attorney’s office to not offer this kind of deal to a person who has refused the breath test. Refusing to blow can cost you big in those cases.

While the conventional wisdom says not to blow when you’re pulled over on suspicion of DUI, that knowledge has slowly become wrong. Just as law offices have advised people on this matter, police departments and district attorney’s offices have changed their processes. By refusing to blow today, you will likely just put yourself in an awkward position, losing the opportunity accept a pretrial deal while costing yourself an administrative suspension in many cases. With a blood test likely coming anyway, taking the breath test is sometimes your best option, especially if you’ve been using drugs of any kind.