Yes, generally, under federal law. Marijuana is still a Schedule I drug under the Controlled Substances Act, and that hasn't changed just because your state has legalized it. So as a general matter, most employers can still test candidates for marijuana before making a hire.
But that federal yes covers less ground than it used to. A genuinely fast-growing number of states now restrict what you can actually do with a positive result, separate from whether you can run the test at all. Those are two different questions. Mixing them up is where employers get into trouble.
The Controlled Substances Act treats marijuana the same way it treats heroin, at least on paper. Schedule I. No accepted medical use, according to federal law, no matter what a state's medical marijuana program says.
That federal classification is why pre-employment marijuana testing, as a practice, is still legal in most places. No federal law bans an employer from screening for it before a hire. State legalization changes what marijuana means for a resident using it on their own time. It doesn't erase the federal drug schedule.
So to say that again a different way: your state can legalize marijuana for recreational or medical use, and testing for it in a pre-employment screen can still be perfectly legal at the same time. Those aren't contradictions. They're two separate legal questions, and this whole article is really about the second one.
Here's the part that's moving fast. A growing group of states have passed laws that don't ban the test itself. They restrict what you can do once the result comes back positive.
The line they're drawing is off-duty legal use versus on-the-job impairment. Several states, California and New York get cited most often, now bar employers from refusing to hire someone based solely on marijuana use that happened off the clock and off company property, where that use is legal under state law.
Actual impairment at work is a different matter. Employers generally can still act on that, in every state I'm aware of.
I'm not going to hand you a final list of which states do this and call it settled. I've said the same thing in earlier articles about credit checks and arrest records, for the same reason. This is one of the fastest-moving corners of screening law right now, and a list that's accurate today can be wrong in six months. Check your specific state's current rule with a lawyer or your background check provider's compliance team before you build a policy around it.
Here's the detail driving a lot of these state laws. A standard marijuana test, urine or hair, detects past use. It doesn't detect whether someone is impaired right now.
THC can show up on a test for days after occasional use, and for weeks after regular use. Someone who used marijuana legally on a Saturday can test positive on a Wednesday with zero impairment on the job. That gap between used it recently and impaired right now is exactly the reasoning states are pointing to when they limit what a positive result alone can justify.
That's worth thinking through even in a state that hasn't passed a specific restriction yet, honestly. A policy that treats every positive test as automatic disqualification is treating a chemistry result like a behavior. It isn't one.
None of the hedging above applies if you're hiring for a role regulated by the Department of Transportation. Commercial drivers, pilots, and other safety-sensitive transportation positions follow federal drug testing rules under 49 CFR Part 40. Those rules don't recognize state marijuana law at all.
Marijuana stays what DOT calls a no-excuse violation for these roles. A medical marijuana card doesn't change that. Neither does living in a state where recreational use is fully legal. That part's not optional to follow, and it's not likely to change anytime soon since it comes from federal safety regulation, not a policy trend.
If you're hiring for a role that isn't DOT-regulated, work out two things before you finalize a drug testing policy. Does your state restrict what you can do with a positive marijuana result. And if it does, does your policy actually separate off-duty use from on-the-job impairment, instead of treating a positive test as automatic disqualification.
Ask any background check provider you're evaluating how they handle marijuana results specifically, not drug testing in general. Some CRAs already build state-specific rules into how they report marijuana results. Others just hand you a raw pass or fail and leave the legal reading to you. That difference matters more here than it does for most other checks, because the law itself is still moving.
If you're not sure your current policy holds up in every state where you hire, that's worth checking now, not after a candidate pushes back on a rejection. All Screeners' matching tool can point you toward providers that build state-specific marijuana rules into their reporting. Want your whole screening program reviewed for gaps like this one? That's what our True Fit consultation is for.