He doesn’t. He can see how you drive and stop though. The point is define bad brakes. There’s a very large grey area and not all will agree. The government is VERY bad at these type of definitions so in the end it just doen’t work. Shops that do improper inspections are a problem and they are plentiful. I repeat that shops ARE NOT making a fortune on inspections.
I see that you don’t live in Texas.
Texas has a set inspection criteria for brakes. Seems pretty comprehensive to me:
http://www.txdps.state.tx.us/vi/inspection/rules_list.asp?itemdrop=Brakes&rejectsubmit=Go
20.02 Brakes. Every passenger car, truck, bus, school bus, and motorcycle shall be equipped with brakes acting on all wheels except:
1. Motor-driven cycles, motor scooters, motorcycle sidecars, or mopeds.
2. Trucks and truck tractors (manufactured prior to 1981) having three or more axles need not have brakes on the front wheels, except that when such vehicles are equipped with at least two steerable axles, the wheels on one steerable axle need not have brakes. However, such trucks and truck tractors must be capable of complying with the performance requirements of this Act.
3. Any vehicle being towed in a driveaway or towaway operation, provided the combination of vehicles is capable of complying with the brake performance requirements, does not require brakes acting on all wheels.
Definition of Terms:
Brake System: A combination of one or more brakes and their related means of operation and control.
Service Brake System: A brake system used for retarding, stopping, and controlling the vehicle under normal operating conditions. This brake is sometimes referred to as “foot brake.”
Parking Brake System: A brake system used to hold and maintain the vehicle in a stationary position. (A positive mechanical means is employed to hold the brake applied when the vehicle is unattended.)
Pedal Reserve: As applied to hydraulic, mechanical, or power assisted hydraulic brakes, this is the amount of distance (total pedal travel) left in reserve when the pedal is depressed to the brake-applied position. (The purpose of the pedal reserve check is to ascertain the degree of the brake adjustment and to demonstrate satisfactory brake actuating system condition).
Equalization: Brakes shall be so adjusted as to operate as equally as practicable with respect to the wheels on the opposite sides of the vehicle.
Driveaway-Towaway Operation: Any operation in which any motor vehicle, trailer, or semitrailer, singly or in combination, new or used, constitutes the commodity being transported when one set or more of wheels of any such vehicle are on the roadway during the course of the transportation, whether or not any such vehicle furnishes the motor power.
4. Inspection Procedure. Service brake performance tests should be conducted on a substantially level, hard, smooth surface road or area that is free from loose material, oil, or grease. Using the service brake only, the stopping ability of the vehicle should be tested by one of the following methods.
a. Service Brake Test
1) On Road (Decelerometer): Mount an approved decelerometer at centerline of vehicle. Level the deceleromoter. At a speed of 20 mph apply service brake firmly. Observe decelerometer reading.
2) On Road (Road Test): At a speed of 20 mph apply service brakes firmly. Observe whether a vehicle comes to a smooth stop within the distance prescribed by the chart, “Required Brake Performance.” Inspector should have firm control of the steering wheel throughout the test.
3) Platform Tester: Drive vehicle onto “drive-on-and-stop” platform tester. Apply brakes firmly at a speed from 4-8 mph without wheel lockup. All braking action must take place on the platforms.
NOTE: Front-wheel drive vehicles are to be checked by road test only unless a platform tester specifically approved by the Department to test front-wheel drive vehicles is used.
These machines may be used to inspect the relative effectiveness of each wheel. There should be braking action on all wheels and the action on any one wheel should be 75 percent or more of the action on the other wheel on the same axle.
4) Roller-Type Brake (Dynamometer-Force Measuring Type):
a) Adjust tire inflation to recommended values.
b) Position vehicle on dynamometer rolls and begin test.
c) Follow Department’s recommended testing procedures.
b. Test Brake Hydraulic System for Leakage.
While vehicle is stopped, inspector should be able to apply a moderate foot force (40-60 pounds in nonpowered systems and 15-20 pounds in power assisted systems).
c. Test Pedal Reserve.
While the vehicle is stopped, depress brake pedal under moderate foot force (40-60 pounds in nonpowered systems and 15-20 pounds in power assisted systems).
d. Condition of Vacuum System.
Visually inspect system for collapsed, broken, badly chafed and improperly supported hoses and tubes, and loose or broken hose clamps.
5. Inspect Service Brakes for and reject if:
a. Vehicle is not equipped with required service brakes.
b. Upon first application, there is less than 2 inches of pedal reserve as determined by the use of an accurate measurement on the fully applied brake pedal of vehicles equipped with conventional brakes.
c. Upon first application, there is less than 1 inch of pedal reserve as determined by the use of an accurate mea-surement on the fully applied brake pedal of vehicles with power brakes (power must be on and operating when tested).
d. On service brakes that cannot be checked with the use of an accurate measurement, there is less than a reserve of one-third of the total travel distance of the brake actuator.
e. Brake pedal height cannot be maintained under moderate foot force (40 to 60 pounds for conventional - 15 to 20 pounds for power) for a period of 1 minute.
f. There is visible leakage or audible seepage in hydraulic lines and cylinders, or any other part of the service brake system.
g. Fluid level in the master cylinder is more than 1 inch below the top of the reservoir or below manufacturer’s recommended level.
h. Hoses or cables are restricted, abraded, crimped, cracked, leaking, frayed, or broken.
i. Brake rods or mechanical parts are missing, broken, badly worn, or misaligned.
j. Brake operating levers or control cables do not operate freely, improperly positioned, or misaligned.
k. Any part of the service brake system has been removed, disconnected, rendered inoperative.
l. There is an obvious metal to metal contact sound when brakes are applied, and upon investigation, drum or disk is being scored.
m. The service brakes do not develop the required total braking force as determined by machine tests.
n. Brakes do not meet requirements for stopping distances for the class of vehicle.
o. The brakes are not equalized as determined from road testing or by machine tests of the vehicle.
p. Brake warning lamp or signal is on or comes on during test.
NOTE: Anti-lock (ABS) lamp or signal which is on or comes on during test will not be cause for rejection.
NOTE: It is imperative that brake system reservoir cover and the surrounding area be thoroughly cleaned before cover is removed for inspection to assure that NO DIRT OR WATER is mixed with the brake fluid.
We also have regs for parking brakes.
http://www.txdps.state.tx.us/vi/inspection/rules_list.asp?itemdrop=Brake+-+Parking