Who enforces HOS regulations?

Law enforcement: Generally, DOT officers are the ones who enforce HOS rules, although any police officer may inspect a driver's logbook. Individual states are responsible for maintaining weigh stations where drivers are pulled in for random vehicle and logbook inspections. Drivers may also be pulled over for random checks by police officers or DOT officials at any time and have their logbooks inspected. While it's not a frequent occurrence, chances are your logbook will be checked every now and then. Be ready for it at all times!
Carriers: In addition to law enforcement and DOT officials, most carriers have their own company policies regarding logbooks. A drivers logs are frequently reviewed by internal auditors for discrepancies or violations. A driver with too many violations might be warned, disciplined, or terminated (terminating a driver usually only occurs after several violations). The increased use of electronic logging devices has forced carriers to crack down on HOS violations even more.