Issues with Automatic License Plate Readers' abilities to accurately gauge new Tennessee standard license plates at night led the Tennessee Department of Revenue to partner with the Department of Safety and Homeland Security for solutions.
The two departments worked with the help of state partners and industry stakeholders to better understand ALPR technologies in the state. They discovered that the readability of plates varied significantly across ALPR models, but daytime readability was not an issue.
At night, the readers use infrared technology to capture images of license plates based on contrasting reflective and non-reflective parts. The contrast of the blue background to reduce the reflective levels of the white backgrounds has not been ideal for some ALPR models.
Troopers tested Tennessee's new plates with adjusted background paint pigmentation levels. They used five brands to represent a wide range of ALPR systems.
After the testing was completed, the state determined that it would not have any plans to change its plates.
The variance discovered in the readers led state officials to determine which of the systems of ALPR technologies will be meeting necessary standards instead.
It will be the responsibility of Tennessee's law enforcement agencies to ensure they utilize the right systems to meet the needs of the new plates.
