Maryland’s drugged driving law is located at Maryland Annotated Code Section 21-902. It states that a person may not drive or attempt to drive any vehicle while he is so far impaired by any drug, any combination of drugs, or a combination of one or more drugs and alcohol that he cannot drive a vehicle safely. It also states in subsection (d) that “A person may not drive or attempt to drive any vehicle while the person is impaired by any controlled dangerous substance if the person is not entitled to use the controlled dangerous substance under the laws of this State.”
In other words, in Maryland it’s a crime to drive while under the influence of a drug. No blood testing standard is established in Maryland – that is, there is no fixed amount of drugs within the blood system that determines conviction. Whether a driver is impaired is determined on a case-by-case basis and at the discretion of the prosecutor.
Maryland’s drugged driving law is directed at the prohibition of "any drug” or combination of drugs that impairs driving ability. It’s not an acceptable defense to a drugged driving charge to claim that the driver is legally entitled to use a controlled substance unless charged with a violation of subsection (d) (see above).
A driver arrested for drugged driving in Maryland will be charged with driving under the influence and subject to DUI penalties. A conviction for drugged driving will be considered as a prior offense for purposes of calculating punishment regardless of whether a subsequent offense is due to alcohol or drugs. Read more about Maryland’s DUI laws.
Yes, there is an implied consent rule for blood testing. The refusal to take the test can be admitted into evidence against the driver.