The police have the right to detain the car when it is overloaded. If road passenger vehicles and freight vehicles are overloaded, they may be detained because there are no other motor vehicle drivers to take the place of driving, and the illegal acts have not been eliminated, and it is necessary to investigate or preserve evidence.

Legal basis: Provisions on Procedures for Handling Illegal Acts of Road Traffic Safety.

Twenty-fourth traffic management departments of public security organs and their traffic police can take the following administrative compulsory measures in the process of law enforcement:

(1) detaining vehicles;

(2) detaining a motor vehicle driver's license;

(3) towing a motor vehicle;

(4) testing the contents of alcohol, psychotropic drugs and narcotic drugs under state control in the body;

(5) Confiscation of articles;

(six) other administrative compulsory measures as prescribed by laws and regulations.

Twenty-seventh in any of the following circumstances, the vehicle shall be detained according to law:

(a) the motor vehicle driving on the road does not hang the motor vehicle number plate, does not place inspection marks and insurance marks, or does not carry the motor vehicle driving license and driver's license with the vehicle;

(2) Suspected of forging, altering or using forged or altered motor vehicle registration certificates, license plates, driving licenses, inspection marks, insurance marks and driving licenses, or using motor vehicle registration certificates, license plates, driving licenses, inspection marks and insurance marks of other vehicles;

(3) Failing to take out compulsory motor vehicle traffic accident liability insurance in accordance with state regulations;

(four) road passenger vehicles or freight vehicles are overloaded;

(5) The motor vehicle is suspected of being stolen or robbed;

(six) the motor vehicle is suspected of being assembled or reaching the standard of scrapping;

(seven) did not apply for the "road transport license for highly toxic chemicals" to transport highly toxic chemicals by road;

(eight) non motor vehicle drivers refused to accept the fine.

If there is a road traffic accident and it is necessary to collect evidence, the accident vehicle may be detained according to law.