Appeals by two sacked truck drivers against separate employers have failed.
One was dismissed for driving dangerously and the other for using drugs.
The Employment Relations Authority found that both had been justifiably sacked.
In the first case, Carey Walters was fired by Tulloch Transport in Dunedin in April
last year after a member of the public complained he had been driving dangerously.
Mr Walters was driving on State Highway 1 in South Canterbury in March last year when he overtook a car in which Senior Sergeant Warren Newbury was teaching his daughter to drive.
The policeman complained to Tulloch Transport that Mr Walters had sped up and dangerously overtaken them near a corner that had yellow no-passing lanes.
When told about the complaint, Mr Walters told his employer: "Yep, I couldn't stop and the driver slammed on their brakes and the car was all over the road so I did pass on the wrong side of the road crossing the yellow lines."
After two meetings with his bosses, Mr Walters was sacked, despite saying he felt that he had been driving safely. However that complaint had been the third against him in two months.
In the second case, Katrina Thomson was sacked by MJD Haulage in Ashburton after testing positive for cannabis use.
She had been at work on January 23 last year when she tripped and injured her shoulder. She was taken to a medical centre in Ashburton and had to give a urine sample as part of normal procedures.
That sample tested positive for THD-acid - an ingredient in cannabis - and as a result, she lost her job.
However, Ms Thomson denied taking cannabis.
"[She] became upset and started crying. She said that the test could not be right as she did not use marijuana," the Employment Relations Authority report said.
Further samples provided by Ms Thomson tested negative for drugs, but she was not given her job back.
That decision was just, the authority said, as it was clear that she had used cannabis around the time that the first test - which was positive - was taken.
