Quick answer: You don’t fight the number — you fight the foundation. Maryland’s radar statute is a single sentence and it imposes no calibration requirement, no operator certification, nothing. All of that has to be established by the officer’s testimony in court. Which means it can be tested — and the most productive question in the room is usually: “How, exactly, did you calibrate it?”
I’m David Waranch. “I wasn’t going that fast” is not a defence. Here’s what is.
What the Law Actually Says (It’s One Sentence)
Md. Code, Cts. & Jud. Proc. § 10-301, in its entirety:
“The speed of a motor vehicle may be proved by evidence of a test made upon it with a device designed to measure and indicate the speed of a moving object by means of radio-micro waves.”
That’s it. That’s the whole thing.
Notice what isn’t in there. No requirement that the unit be calibrated. No requirement that the officer be trained or certified. No requirement that records be kept. The statute simply says radar evidence may be used.
So where does the reliability come from? From the officer, on the stand, under oath. The State has to build that foundation live, in the courtroom, out of testimony. And a foundation built out of testimony is a foundation that can be taken apart.
How Radar Actually Works
Worth understanding, because the weaknesses fall out of the physics.
A radar gun emits radio waves. They strike a moving object and bounce back. Because the object is moving, the returning waves come back at a shifted frequency — the Doppler shift — and the unit converts that shift into a speed.
- Stationary radar. The officer sits still, often out of sight, and the unit reads approaching traffic. By the time you see the patrol car, the reading has already been taken.
- Moving radar. Used from a moving patrol car. It has to calculate the patrol car’s own speed and yours, and subtract one from the other. That’s two measurements instead of one — and twice as many ways to go wrong.
Radar does not identify which car it read. It returns a number. Matching that number to your vehicle is the officer’s judgment — and on a busy road with several vehicles in the beam, that judgment is a fair question.
The Tuning Fork Question
This is the one that wins cases, and it works because most officers answer it honestly and most drivers never think to ask.
A radar unit is supposed to be calibrated before and after each shift. Ask an officer whether they calibrated the unit and you’ll get a confident yes. Ask how, and the answers diverge sharply.
A great many officers believe calibration means flipping the unit’s internal test switch. It doesn’t. A proper calibration requires a tuning fork — a precisely machined fork that, when struck and held in the beam, should produce a known speed reading. If the unit doesn’t return that number, it isn’t reliable.
And the forks themselves are delicate. They have to be kept in their case, protected from moisture, knocks and temperature swings. A fork rattling loose in a glovebox for two years is not a calibration instrument — it’s a piece of metal.
So the sequence is: Did you calibrate it? How? With what? When was the fork last checked? Where is it kept? Do you have the records?
If the answer is “I flipped the switch,” the State’s foundation has a hole in it. That is not a technicality. It goes to whether the number on your citation means anything at all.
The Other Places These Cases Break
- Operator training. The officer has to be qualified to use the device. Not just to hold it — to use it, and to know its limitations.
- Target identification. Which vehicle was in the beam? Was there traffic around you? Was a larger vehicle nearby? Radar tends to favour the strongest return, which is often the biggest object — not necessarily the closest one.
- The visual estimate. Officers are trained to visually estimate speed before confirming it with radar. If the estimate and the reading are far apart — or if there was no estimate at all — that’s worth exploring.
- Maintenance records. Not just the daily calibration. When was the unit last serviced by the manufacturer?
- The officer doesn’t appear. The State’s case is the officer. If they don’t come, there’s usually no case. This happens more than people imagine — and it’s the single most common way these tickets end.
The Mistake That Throws All of This Away
Read your citation. If it’s payable, you have four options, and one of them is a trap.
Requesting a “guilty with an explanation” hearing sounds like the sensible middle path. But under § 26-204(b)(2)(ii), asking for one expressly waives your right to a trial of the facts and “any right to compel the appearance of the police officer.”
Everything on this page — the calibration, the tuning fork, the target identification, the officer simply not turning up — all of it disappears the moment you tick that box. You have already pled guilty. You’re only arguing about the fine.
Request the trial. Read more on payable versus must-appear citations.
What’s Actually at Stake
| How fast over | Points |
|---|---|
| Under 10 mph over | 1 |
| 10 mph or more over | 2 |
| 20+ mph over a 65 limit | 5 |
| 30+ mph over the posted limit | 6 |
And that last row is now far more serious than it used to be. Since the Sergeant Patrick Kepp Act took effect on 1 October 2025, driving at least 30 mph above the posted limit is reckless driving by definition — 6 points, up to 60 days in jail, a $1,000 fine, and a mandatory court appearance.
If your radar reading is 30 or more over, the accuracy of that number isn’t an academic question. It’s the difference between a fine and a jailable charge.
Related Questions
- “I wasn’t going that fast” — what to do when the ticket lists the wrong speed
- How the Maryland point system works
- Payable or must-appear — which ticket do you have?
Frequently Asked Questions
Can you beat a radar speeding ticket in Maryland?
Yes, and more often than people expect. But not by arguing about the number. You beat it by attacking the foundation — calibration, the tuning fork, operator training, target identification — or because the officer doesn’t appear.
Are radar guns accurate?
A properly calibrated unit, correctly operated, on a clear target, is accurate. Every one of those conditions is a question the State has to answer, and any one of them can fail.
Can I request the calibration records?
Yes, and you should. Their absence is meaningful. So is their content.
Do I have to go to court?
For an ordinary payable speeding ticket, often not — I can enter my appearance, request the trial, and go for you. If your reading is 30 or more over the limit, that’s now a reckless driving charge and you’ll need to appear.
Don’t Pay It Yet
Paying is pleading guilty. The points go on, your insurer sees them, and every question on this page goes unasked.
Send me the citation and I’ll tell you honestly whether it’s worth fighting.
Toll-free 1-877-566-2408. Hablamos Español. More on how I defend Maryland speeding charges.
Last updated: July 2026