blood alcohol legal limit

Blood Alcohol Legal Limit

Many people are probably familiar with the phrase ‘blood alcohol’, but what does it really mean, and what are the legal issues pertaining to it? Simply put, blood alcohol is a measure of the amount of alcohol in a person’s system, and therefore the amount of impairment that person is experiencing. Blood alcohol content, commonly referred as BAC, goes up with every alcoholic beverage a person consumes, and it is measured by calculating the weight of ethanol, in grams, per 100 milliliters of blood. For instance, a BAC of .10 would indicate that the individual in question would have one part alcohol per thousand parts blood.

How Police Measure BAC

The interesting thing about blood alcohol is that it can be detected through blood tests, of course, but it can also be detected by urine and breath tests as well. When a person is driving erratically and an officer thinks the driver might be intoxicated, the officer will perform a field sobriety test, which may or may not include a device called a breathalyzer. These ingenious devices measures blood alcohol content by capturing alcohol content in the breath of an individual and using the concentration of alcohol in the breath to calculate the level of alcohol in the bloodstream. Breathalyzers are an important tool for police officers to prove a driver is intoxicated, because they must prove the driver is over the blood alcohol legal limit.

The BAC Legal Limit

The blood alcohol legal limit is designed to be a separation point between those deemed too intoxicated to operate a motor vehicle and those under the limit. The actual figure is .08, which typically only takes a few alcoholic drinks to achieve. For example, a 140-lb woman would have a BAC of .10 if she had just three alcoholic drinks. BAC does go down over time as the body filters and processes it, but the rate is so slow that it takes up to six hours for someone barely over the legal limit of .08 to become sober. This is one of the main reasons why law enforcement officials take advantage of breathalyzer technology. It allows them to set a numerical limit and gives them proof that a driver is or is not over the limit. Such evidence is nearly impossible to deny in court.

Consequences of Intoxication

First, it should be noted that the legal BAC limit only applies to drivers operating a motor vehicle. It is perfectly legal for passengers to exceed the limit, but the driver must remain sober. If a driver is caught over the legal limit and is found guilty of driving under the influence (DUI) in court, which is the common outcome thanks to breathalyzers, there are several potential consequences. Depending on the severity of the offense, DUI could include up to six months of jail time and fines from $500 to $2000. Someone convicted of DUI can also expect to have their driver’s license suspended for a significant period of time and up to three years for repeat offenders.

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