By Leisa Wintz, Esq. · Family Matters Law Group, P.A. · FL Bar No. 64399 · 18 years practicing Florida family law
If you have a Florida medical marijuana card and you’re headed into a custody case — or your co-parent has one and you’re worried about your kids — here is the short answer: the card itself is almost never the issue. What a Florida judge cares about is whether a child is safe and well cared for during each parent’s time. The parents who get this wrong fight about drug tests. The parents who get it right write parenting plans about behavior.
I’ve spent 18 years practicing family law in Florida, and this question is coming up more every year. Let’s walk through how it actually works.
Can I lose time-sharing in Florida because I have a medical marijuana card?
Not because of the card alone. Florida decides every parenting issue under the best-interests standard in Fla. Stat. § 61.13, and one of the factors a court weighs is each parent’s demonstrated capacity to provide a safe, stable environment — including whether substance use impairs their parenting. The question is never “does this parent use marijuana?” It’s “is this parent impaired while caring for the child, and are the products stored and used safely?”
That cuts both ways. Holding a valid card doesn’t immunize you if you show up to exchanges impaired or leave gummies on the counter. And if you’re the concerned parent, pointing at the card — or at a positive test — usually isn’t enough by itself.
Why doesn’t medical marijuana work like a prescription drug in a custody case?
This is the part almost everyone misses, including a lot of lawyers.
When a parent takes a prescribed stimulant or other traditional medication, parenting plans often use language like this: the parent may test positive, but the levels must be consistent with the prescribed dosage. A random test can confirm they’re taking the medication as prescribed, not abusing it. Even that approach is not as reliable as it sounds — a test gives you a range, not a number, and levels can vary drastically from one person to another on the identical prescription.
Medical marijuana breaks even that imperfect model, because in Florida a qualified physician doesn’t write a prescription with a daily dose. Under Fla. Stat. § 381.986, the physician issues a certification, and the patient purchases within supply limits — there is no “take 10mg twice daily” on the bottle to measure a test result against. On top of that, THC is fat-soluble: it can show up on a test days or even weeks after use. So a positive test tells you almost nothing about whether the parent was impaired on Tuesday afternoon when they had the kids.
Can it be done anyway? Sometimes, partially. A medical professional can testify to what an average quantity or usage pattern would look like for a patient with a particular certification, and frequent-use patterns can be distinguished from occasional ones. But it’s expert-dependent, expensive, and imprecise — which is exactly why “prescribed dosage” language borrowed from stimulant cases tends to fall apart with marijuana.
What does a judge actually look at instead?
Evidence of impairment and risk around the children, not chemistry. Things like:
- Use during time-sharing, or right before picking the kids up
- Driving with the children after using
- Products left unsecured where a child can reach them (this is the one that produces emergencies — edibles look like candy)
- Smoking or vaping in the home or car with the children present
- A pattern of use that interferes with supervision, school routines, or medical needs
If none of that is happening, a judge is unlikely to restrict time-sharing over lawful medical use. If it is happening, the card won’t save anyone.
What should a parenting plan actually say about medical marijuana?
Write rules about behavior, not test results. Provisions that work in a supervised or safety-focused parenting plan look like this (adapted to the family, the certification, and the level of concern):
- Timing: No marijuana use during time-sharing or within a defined window before it begins.
- Driving: No driving with the children after use, full stop.
- Storage: All marijuana products kept in a locked container, out of reach and sight of the children, at all times.
- Method: No smoking or vaping in the presence of the children, in the home while they are present, or in any vehicle used to transport them.
- Documentation: The parent maintains an active, valid certification and registry status, and provides proof on request.
- Testing, used correctly: If testing is included, it’s tied to observable impairment or specific violations — not framed as a pass/fail “prescribed level” test, because no such level exists.
- Escalation: What happens on a documented violation — make-up time, supervision, or review — spelled out in advance.
Florida’s Supreme Court-approved safety-focused parenting plan form exists for exactly these situations, and these provisions slot into it. The goal is a plan the judge can read and think: whatever this parent’s medical treatment is, this child is safe. That’s the whole game.
What if the other parent is the one using?
Document behavior, not status. Dates, times, what you observed, photos of unsecured products — not “they have a card and I don’t like it.” Ask for the behavioral provisions above rather than a blanket ban a court is unlikely to order against lawful medical use. And be realistic about testing: demanding random tests that will always come back positive proves nothing and spends your credibility. Targeted, well-drafted provisions protect your kids better than outrage does.
Frequently asked questions
Can a Florida judge order a parent to stop using medical marijuana entirely?
Courts can restrict what happens around the children — timing, storage, driving, method of use. A blanket ban on a parent’s lawful medical treatment is a much harder ask and generally requires evidence that use itself endangers the child.
Does a positive THC test mean a parent fails a drug test under a parenting plan?
Not if the plan is drafted correctly. THC can remain detectable for days or weeks, so a positive result alone doesn’t show impairment during time-sharing. Plans should define what a violation actually is.
Is a medical marijuana certification the same as a prescription in Florida?
No. Under Fla. Stat. § 381.986, physicians issue certifications with purchase limits — not prescriptions with a daily dosage. That difference is why dosage-based testing language doesn’t translate.
What is a safety-focused parenting plan in Florida?
A Florida Supreme Court-approved parenting plan format designed for cases with safety concerns, allowing conditions like supervised time-sharing and specific protective provisions while the concerns are addressed.
Do I need a lawyer to add marijuana provisions to my parenting plan?
You can propose them yourself, but drafting matters enormously here — vague or test-based language creates the exact fights it was supposed to prevent. Even one coaching session on the language can change the outcome.
The bottom line
A medical marijuana card is not a custody problem. Impairment around your kids is. Florida judges protect children, not test results — so build a parenting plan that proves your child is safe: no use around time-sharing, no driving after use, locked storage, nothing smoked around the kids. Written rules about behavior beat fights about chemistry every time.
This article is general information about Florida law, not legal advice for your specific situation. Every case is different — talk to a Florida family law attorney about yours.