Driving under the influence of alcohol or drugs (DUI) is a crime or offence according to the laws of most countries. DUI increases the risk of traffic accidents as well as the severity and outcome of injuries that result from them. Some countries have a sophisticated control system to monitor DUI of alcohol in all traffic accidents. There is variation between different countries regarding the concept of driving under the influence of alcohol as well as the legal limits of Blood Alcohol Concentration (BAC) and the requirements to test the victims of accidents. This paper reviews the limit values for BAC in German traffic law (Administrative Offences Act), which stipulates a BAC value of 0.50 mg/g and a breath alcohol value of 0.25 mg/L as a marginal value for the application of punitive measures. German criminal law defines the minimum BAC values of relative unfitness to drive and absolute unfitness to drive as 0.3 mg/g and 1.10 mg/g, respectively (1.60 mg/g for cyclists).The minimum BAC values representing significant impairment and absolute impairment in criminal cases are 2.00 mg/g and 3.00 mg/g, respectively. Different penalties and legal consequences result according to the BAC level of an offender. In contrast, only eight out of twenty-two Arab countries recognise BAC limit values only in traffic laws. In Jordan, the BAC limit is 0.75 mg/g (0.08 g/dL).in the UAE, the BAC limit is 0.094 mg/g (0.01 g/dL), while Egyptian law does not recognise BAC values in the application of sanctions: the mere presence of alcohol in blood, regardless of its concentration and effect, is a sufficient and adequate condition for punishment. Accordingly, this study encourages lawmakers in Arab countries to define the limit values for BAC when investigating any crime in general and traffic offences in particular, in close cooperation with forensic doctors and toxicologists. It urges them to consider different BAC and their effects in relation to traffic offences. It also encourages them to take into account the principle of hierarchy in criminal liability when a crime is committed under the influence of alcohol.