In Washington and Colorado where pot has been legalized, police officers normally rely on blood tests to know whether a person has been smoking or using pot. The new breath tester is designed to make testing a stoned driver easier and faster.

The use of pot among drivers have caused a deep concern in Washington since it has legalized the recreational use of marijuana two years ago. Apart from the blood tests, police also had to rely on the traditional standardized field sobriety tests wherein a driver would be asked to walk in a straight line.

Study shows that only 30 percent of those who are found to be influenced with marijuana's THC content failed the sobriety tests. Moreover, blood test results would need up to twenty-four hours before they are released. THC is tetrahydrocannabinol, the active ingredient in pot responsible for its psychological effects.

Police needed a better and faster way to determine if a driver has been on the road while under the influence of drug. While the marijuana breath testing device will not be able to display the level of THC in the body, it will at least help the law enforcement in discerning on some presence of active THC.

"We believe, at least initially, that it would lower the false positives that an officer would have," said Herbert Hill, chemistry professor at Washington State University. "They would have a higher level of confidence in making an arrest."

Hill and doctoral student Jessica Tufariello are working on a handheld breath testing device that features a technique known as 'ion mobility spectrometry' in determining the presence of THC. The research team plans to wrap up the laboratory tests this year and eventually produce a prototype marijuana breath tester. The group plans to begin testing human breath between the months of January and June in 2015.

At a meeting held by the Senate Law & Justice Committee on Nov. 21, some lawmakers have lauded the research team for their breakthrough device.

"WSU is going to be at the forefront, it seems to me, of supplying this kind of science and the technology that's based on it to police all over the country," said Sen. Adam Kline, D-Seattle.

 In 2012, the Washington State Toxicology Laboratory stated that 18.6 percent of the blood samples that were taken from impaired drivers in Washington were found to be positive with THC. In 2013, the number increased to 25 percent which was recorded a year after the Washington Initiative 502 took effect.