While Pennsylvania law enforcement officers can use breath and blood tests to accurately gauge a driver’s level of alcohol impairment, there are currently no tests that reliably measure a driver’s level of marijuana impairment. However, that could soon change.

Scientists at the University of Texas at Dallas have developed sensor strips and an electronic reader that can detect THC, which is the substance in marijuana that makes people high, levels in human saliva. The sensor strips are coated with an antibody that can isolate THC compounds in an individual’s saliva sample. When the strip is placed in the electronic reader, the device applies a specific voltage that interacts with the THC compounds. This information is then converted into a THC concentration level.

Research has shown that the device can accurately measure both high and low concentrations of THC, something that no other cannabis test prototype has been able to do. It is also noninvasive and requires just five minutes to complete, making it appropriate for roadside use. Because marijuana is still illegal in Texas, the scientists have not been able to test the device on saliva from people who have consumed marijuana. Instead, they’ve been forced to use saliva samples that have been infused with THC. However, they soon plan to partner with researchers in states where marijuana is legalized to test the device on actual cannabis users. The research was presented on the American Chemical Society SciMeetings website.

Pennsylvania residents charged with impaired driving might assume they have limited legal options. However, a DWI defense attorney could review a defendant’s case and look for ways to fight the charges in court. In some cases, the attorney’s actions might cause the charges to be dismissed. In others, they may lead to a plea deal that reduces the charges.