sobriety tests that i can administer or my patrolman are going to show impairment. it s then later on when you get into processing where you re given the opportunity to do the breathalyzer test where it s determine it s not necessarily alcohol, it s something else, and that s where i come in as a drug recognition expert. once we figure out it s not an alcohol dwi, i do a standardized set of 12 tests which are able to determine what drug can category you re under the influence of which includes cannabis. reporter: so you ve obviously been trained in this, but it is different than alcohol where you have a standardized test and a limit, a breathalyzer, blowing a .08, you re in trouble. you don t have the same for marijuana, so what challenge does that present when it comes to identifying that this person shouldn t be driving? it makes it fairly simple to still identify, it s when we go to court and we have to prove it that it becomes more channeling. obviously, the breathalyzer test h