Under New Jersey law, a person will be found guilty of driving while intoxicated (DWI) if they drive a motor vehicle while they have a blood alcohol concentration (BAC) of 0.08% or higher. This figure, 0.08%, is commonly called “the legal limit,” but that name can be a bit misleading. In fact, in some cases people can be convicted of DWI even if they were found to have a BAC of less than 0.08%.
Technically, a person could be convicted on DWI charges even without the evidence of a BAC test. Without it, the prosecution would just rely on the reports and testimony of the arresting police officers. But the prosecution would have a tougher time winning a conviction with this evidence alone. This gives a hint of how a person accused of drunk driving might be able to use a defense strategy.
What is BAC?
Many factors go into making up a person’s blood alcohol concentration, and even more factors are involved in the relationship between BAC and the effects of drunkenness. Some of these factors include:
- The number and potency of alcoholic drinks consumed
- The amount of time in which the drinks were consumed
- The amount of time that elapsed between consuming the alcohol and being tested for BAC
- The size and weight of the person
- Any medications the person has taken
- The sex, age and general health of the person
At lower levels of BAC, such as 0.01 %-0.03%. an average person may show no outward effects of drunkenness, but at 0.07% and higher, the person will experience some impairment of reasoning and balance. They will be slower to react to sudden changes, and their judgement may be impaired. Driving in this condition is considered unsafe.
BAC is typically measured using a chemical breath test device at the time of the suspect’s arrest.
This breath test reading can be very strong evidence in the case against the suspect. One common defense strategy is based on attacking that evidence. If a defendant can show that the BAC reading was not trustworthy, they may be able to have the evidence of this test suppressed from court.