A Washington State truck driver has pleaded guilty to vehicular homicide charges after a load of logs came loose and crushed a car, killing two occupants.

An investigation revealed that a logging truck driven by Garland Massingham was almost four tons above its legal weight limit and that bolts securing the load had failed. Witnesses reported that Massingham was also driving at unsafe speeds and he was found to have methamphetamine in his system following the Oct. 4, 2005 incident near Hoquiam, WA.

Two University of Washington seismologists, Anthony Qamar, 62, and Dan Johnson, 46, were killed. Massingham faces a maximum of 4.5 years’ jail time.