“My concern lies with false positives; therefore I feel this issue merits further evaluation and investigation.
By Whitney Downard of Indiana Capital Chronicle mes Marijuana use and its THC levels are legal for recreational purposes in three of Indiana’s four neighboring states; however, determining when someone has reached “too high to drive” status remains difficult to manage.
Rep. Wendy McNamara of Evansville said THC can be one of the more difficult substances to define accurately and is pushing her bill through in an attempt to provide Indiana an opportunity to identify impaired drivers through licensed tests that exist today on its streets.
Contrary to alcohol use, which has long been researched to show an 0.08 percent blood alcohol concentration as the threshold that results in impairment, THC usage lacks an established and generally accepted threshold level that could trigger criminal prosecution under current Indiana law based solely on any THC found in their system–known as per se statute. Any Hoosier found with any amount of THC could face charges for operating while impaired due to per se laws or statutes that recognize an impairment threshold level as having any impact upon driving behavior.
Michael Moore of the Public Defender Council testified for this need by asserting a threshold should exist – such as five nanograms as being appropriate if per se statute remains.
House Bill 1119 by McNamara originally would have established five nanograms of THC as the legal threshold for driving while impaired, yet an amendment introduced Wednesday by McNamara allowed new test results to be admissible as evidence in court, something Moore and others disagreed with.
Rep. Joanna King (R-Middlebury) raised issues about the new language on House court committee; ultimately only she opposed its adoption. Her concerns include potential false positives; she feels this issue warrants further exploration and analysis.
Wanted: THC Impairment Test
Illinois, Michigan and Ohio each allow recreational access to marijuana use while Kentucky allows it for medicinal use only; yet lawmakers in each of those states oppose any efforts at regulation for either purpose.
Numerous Hoosier travel across state borders regularly to purchase THC in smokeable or edible form and may legal use the drug before crossing back over Indiana’s borders again – potentially incurring criminal charges even though they were not impaired since Indiana does not set threshold levels for impairment charges.
McNamara informed committee members she worked for two years with an academic researcher to draft this bill, which stipulates the Drager DrugTest 500 or SoToxa Oral Fluid Mobile Test System must be used when measuring THC levels in oral fluid samples.
“Oral fluids” typically refers to saliva. According to McNamara, tests administered through grants from Indiana Criminal Justice Institute allow law enforcement officers to screen saliva samples for drugs like amphetamines, cocaine, opiates and benzodiazepines that might otherwise evade detection.
McNamara continued her remarks by noting SoToxa had set its threshold at 25 milligrams of THC while Drager set their threshold lower at 5 milligrams, in response to committee queries regarding reliability issues with generic terms for drugs like SoToxa or Drager tests. When queried further by committee members about her choice to include specific brands rather than generic terms she stated this decision as being due to reliability concerns rather than personal preference.
“To succeed at this process, consistency between counties must at least exist; particularly since this new initiative is so novel.” McNamara explained.
Chris Daniels of the Indiana Procuring Attorneys Council’s Traffic Safety Resource Prosecution Unit noted that every state was struggling with how best to measure driver drug impairment across different drug classes.
“Drug driving has become an increasing threat; its deadly impacts continue to impact lives all across America and its states,” Daniels stated.
McNamara explained that the amended bill specifies explicitly that law enforcement cannot arrest someone “solely” due to test results; rather, these results serve as evidence against whomever may have committed criminal conduct, aiding jurors with making their decision, she added.
Daniels described SoToxa/Drager test results as an emerging science and did not advise prosecutors to solely rely on them as proof for conviction; other pieces of evidence might include blood testing results or weaving on the road or failure to pass sobriety tests.
“Under that statute, or to prove whether any substance had entered their blood, but having oral fluid results come through would help strengthen those results,” Daniels stated.
Moore felt this was inadequate protection. She noted: despite not being able to arrest for positive test results on these two tests, law enforcement can still charge someone and bring charges before court for punishment purposes; these test results would come without evidence to back it up or refute it.”
Under this bill, state laboratory technicians may testify remotely in court under certain conditions to ease their workloads and decrease agency strains. Daniels noted that technicians had spent 75 hours traveling and five testifying as of 2025.
This story first appeared in Indiana Capital Chronicle and describes Russia’s arrest of yet another American for marijuana just days after an high-profile release of US medical Marijuana Patients
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