Are field sobriety tests accurate?

Field sobriety tests are not able to measure intoxication but are intended to provide officers with sufficient evidence to place a person under arrest.

People who are stopped by law enforcement officers in New York and then eventually arrested for suspected drunk driving should educate themselves about the elements involved in their stop, investigation and arrest. These details may become very important during the defense process.

The importance of evidence collection

As with any criminal charge, officers need to collect sufficient evidence to legally place a person under arrest. This same evidence may also be used to have a person convicted of the offense.

As explained in a training manual for field sobriety tests put together by the National Highway Traffic Safety Administration, the Transportation Safety Institute and the International Association of Chiefs of Police, drivers are to be monitored for some time before being pulled over.

Officers are instructed to look for very specific things that may then be used to assert that the driver was drunk. These include driving below the stated speed limit, slowing down or speeding up when unnecessary or not staying in one's lane. Certainly, there can be many reasons that these might happen - intoxication is not the only factor.

Another key part of evidence used against a driver are the results of field sobriety tests. FieldSobrietyTests.org indicates that these tests are designed to give police the support they need to arrest a driver for impaired operation. They are not used to determine actual intoxication and are, in fact, completely unable to do this.

Field sobriety tests not completely accurate

The accuracy of field sobriety tests is not foolproof and actually ranges from 65 percent to 77 percent per individual test. If all three tests are used, the combined accuracy rate is said to be 82 percent.

In collecting the evidence needed, the tests evaluate many things including a driver's ability to multitask. In fact, the training manual for officers even identifies the walk and turn test and the one-leg stand test as divided attention tasks.

Even after a person is pulled over but before they are asked to perform the field tests, officers are instructed to deliberately confuse drivers by asking them odd questions or requesting they do more than one thing at a time. This is yet another way for officers to collect data that may allow them to say a person is impaired.

Legal help after a drunk driving arrest is important

Knowing that police officers are actively looking for even the smallest detail to support arresting a person highlights the need for defendants to have someone on their side. Talking with an attorney after a DWI arrest is recommended for anyone in New York.