The short answer
Two other thresholds matter: commercial drivers face a 0.04 limit, and drivers under 21 are held to zero tolerance — Maryland restricts an under-21 licensee from driving with any alcohol in the blood, not merely 0.02.
What each BAC number means
| BAC | What it may mean in Maryland |
|---|---|
| Below 0.07 | A charge may still be possible if police claim other evidence shows impairment. |
| 0.07 | May support a DWI allegation. |
| 0.08 or higher | Meets Maryland’s per-se DUI threshold. |
| 0.15 or higher | Can affect MVA consequences and ignition-interlock options. |
A BAC chart is only an estimate
Weight, food, time, medications, body composition, and drink size all affect alcohol concentration. A chart cannot tell you whether you are safe to drive and cannot predict a test result.
Why the test result may not tell the whole story
- The device may not have been maintained or used correctly.
- The required observation and testing procedures may not have been followed.
- Medical conditions can affect breath-test results.
- Your BAC may have been rising between the traffic stop and the test.
- Blood samples can raise collection, storage, and chain-of-custody issues.
Frequently asked questions
What is the legal alcohol limit in Maryland?
Maryland’s per-se limit is 0.08. At 0.08 or higher you are considered under the influence per se, which means the State does not need extra proof of impairment. A result of 0.07 can support the lesser DWI charge. Commercial drivers face a 0.04 limit, and drivers under 21 are subject to a zero-tolerance alcohol restriction.
Is 0.07 a DUI in Maryland?
No. Maryland treats 0.07 as evidence of driving while impaired (DWI), not DUI. Under Maryland’s evidence rules, a result of at least 0.07 but less than 0.08 is prima facie evidence that the driver was impaired by alcohol. It is a rebuttable presumption — which is exactly the kind of finding a defense attorney can challenge.
What is the difference between a DUI and a DWI in Maryland?
They are two separate offenses. DUI covers driving under the influence and carries the heavier exposure — up to 1 year and a $1,000 fine on a first offense, with 12 points and possible revocation. DWI covers the lesser standard of being impaired by alcohol — up to 2 months and a $500 fine on a first offense, with 8 points. Which one is charged often turns on the test result and the officer’s observations.
Can you be charged with a DUI below 0.08 in Maryland?
Yes. A number below 0.08 does not end the case. Prosecutors can still pursue a DWI charge using other evidence of impairment — driving pattern, field sobriety tests, body-camera video, and officer testimony. This is one reason a low reading is worth reviewing rather than assuming the case is minor.
Does a BAC chart prove what my BAC was?
No. A chart is an estimate built on averages. Weight, food, timing, medications, body composition, and drink size all change the result, and none of that is captured by a grid. A chart cannot tell you whether you were safe to drive and it cannot predict or disprove a test result.
What to do after a DUI or DWI arrest
- Keep every citation, test paper, and temporary-license document.
- Write down what happened while it is fresh.
- Do not post about the stop or try to explain it online.
- Follow the deadline printed on your MVA paperwork and speak with counsel promptly.
Learn more about our Maryland DUI and DWI defense practice, or call 410.268.5515.
Reviewed by Mandeep S. Chhabra, Managing Member, August 2026. This article provides general information about Maryland law and is not legal advice.