Is it really illegal to lie down in a moving vehicle? (not if you're driving)

[tiltypig]

I heard for the first time the other day that it’s supposedly illegal to lean the passenger seat back and lie down while riding in a moving vehicle, even if you’re wearing your seatbelt. I had never heard that before. Is this true (in California)? Is it some kind of weird permutation of the general seatbelt laws?

[Duckster]

(d) (1) A person may not operate a motor vehicle on a highway unless that person and all passengers 16 years of age or over are properly restrained by a safety belt. This paragraph does not apply to the operator of a taxicab, as defined in Section 27908, when the taxicab is driven on a city street and is engaged in the transportation of a fare-paying passenger. The safety belt requirement established by this paragraph is the minimum safety standard applicable to employees being transported in a motor vehicle. This paragraph does not preempt any more stringent or restrictive standards imposed by the Labor Code or any other state or federal regulation regarding the transportation of employees in a motor vehicle.

Source: http://www.dmv.ca.gov/pubs/vctop/d12/vc27315.htm

Now if the phrase, “properly restrained by a safety belt,” is further defined in the law, then perhaps it is illegal to sit in a reclined position.

According to http://www.dot.ca.gov/hq/opo/safety/safetymanual/Chap_17-2000.doc …

This Departmental policy is based on the California mandatory seat belt law as contained in the California Vehicle Code (CVC) Section 27315(d)(1), which states in part:

“No person shall operate a . . . motor vehicle on a highway 
unless that person and all passengers . . . are properly 
restrained by a safety belt.”  

Supervisors shall instruct their employees (drivers/operators and/or passengers) that they must wear their seat belt and shoulder harness while the vehicle is in operation.

The seat belt and shoulder harness shall be used in accordance with the manufacturer’s instructions.

I think the last part is the kicker. If your vehicle manual spells out that wearing a seat belt while sitting in a reclining position is ill-advised, then perhaps it is also ilegal as well under California law.

Of course, IANAL and I may be misinterpreting the above regs.