California has two main speeding laws, and they work differently. Knowing which one you are charged under matters, especially when speeding was the reason for a DUI stop. I am Joel Brand, and here is the difference between Vehicle Code 22349 and Vehicle Code 22350.
VC 22349: the maximum speed law
Vehicle Code 22349 sets absolute maximum speed limits, 65 miles per hour on most highways and 70 where posted. It is a flat numerical ceiling. You violate it simply by exceeding the limit, regardless of how safely you were driving or what the conditions were. The proof is essentially a number from radar, lidar, or pacing. Because everything depends on that number, the reliability of the measurement is the whole case: the calibration of the device, the training of the operator, and, for radar enforcement, whether a current engineering and traffic survey exists, without which the speed evidence can be excluded as an unlawful speed trap.
VC 22350: the basic speed law
Vehicle Code 22350 prohibits driving faster than is reasonable and prudent for the conditions. It is not tied to a number, so you can violate it even while under the posted limit if your speed was unsafe for the weather, traffic, or road, and conversely, exceeding the limit slightly in perfect conditions is judged differently. It is a flexible, judgment-based standard. That flexibility cuts both ways: it gives an officer broad discretion to cite, but it also gives the defense room to argue that the speed was perfectly reasonable for clear, dry, empty conditions.
The practical difference
The simplest way to remember it: 22349 is about an absolute number, while 22350 is about safety for the conditions. A 22349 case usually rises or falls on the accuracy of the speed measurement. A 22350 case turns on the more subjective question of whether the speed was actually unsafe, which gives the defense more room to argue and the officer more discretion to cite. In practice, prosecutors sometimes lean on whichever statute is easier to prove on the facts, and recognizing which one is actually charged tells me immediately where the weak points are.
How the speed is actually measured
Both statutes depend on establishing how fast you were going, and none of the methods is infallible. Radar can pick up the wrong vehicle in traffic or be thrown off by interference. Lidar requires a steady aim and proper calibration. Pacing depends on the officer maintaining a constant distance while reading their own speedometer, which is itself subject to error. I request the calibration and maintenance records for any device, the operator's training and certification, and the conditions under which the reading was taken, because a measurement that cannot be shown to be reliable should not support either charge.
The speed-trap defense
A particularly powerful and underused tool applies to radar enforcement. California's speed-trap law generally requires that a posted limit enforced by radar be justified by a current engineering and traffic survey. When the agency cannot produce a valid, up-to-date survey for the location, the radar evidence can be excluded entirely, which can defeat the speeding charge and, where speed was the stated reason for the stop, support a challenge to the stop itself. I check for a valid survey in every radar case, because its absence can quietly dismantle the prosecution's proof.
Why it matters in a DUI
Either statute can be the stated reason for the traffic stop that leads to a DUI investigation, and a very high speed can become an excessive speed enhancement on a DUI conviction. In both, the key DUI question is whether the stop was lawful. If the speeding claim does not hold up, a motion to suppress can challenge the stop. Both add a point under the DMV point system. And in both, it is worth remembering that speeding, by itself, is not evidence of impairment, plenty of sober drivers speed, so a clean driving pattern apart from the speed can actually cut against the prosecution's impairment theory.
When speed is used to suggest impairment
Prosecutors sometimes argue that a high speed shows the driver was impaired and not thinking clearly. That inference is weaker than it sounds. Speeding is among the most common things sober drivers do, and a driver who was speeding but otherwise driving normally, holding the lane, responding promptly to the lights, stopping safely, actually presents a picture that undercuts impairment rather than supporting it. I make sure the speed is treated as a traffic question and not allowed to substitute for the proof of impairment the prosecution must establish through the chemical and field evidence. Separating the two keeps a speeding allegation from doing work it was never capable of doing.
The excessive-speed enhancement
A very high speed combined with reckless driving can trigger the excessive speed enhancement, which adds mandatory jail to a DUI sentence. This makes the speed allegation matter twice: once as the possible basis for the stop, and again as an aggravating factor at sentencing. Because the enhancement requires both an excessive speed and reckless driving, contesting either element, the accuracy of the speed measurement or whether the driving was genuinely reckless, can defeat the enhancement even where the underlying DUI stands. I treat the speed evidence with that double significance in mind from the start.
How I use the distinction
Identifying which statute is charged tells me where to attack, the measurement in a 22349 case, the reasonableness judgment in a 22350 case, and whether the stop itself was justified. It is part of the approach in my top DUI defenses. I treat the speeding allegation and the DUI as connected but separate questions, holding the prosecution to its proof on each rather than letting a speed reading stand in for evidence of impairment it does not actually supply.
Speeding tied to a DUI stop?
Which statute applies, and whether the stop was lawful, can shape your whole case, and I review both with you. Use the free case analysis on this page, or call me directly at (888) 271-6644. I answer my own phone, 24/7.