Edinburgh city council has found “strong concerns” that staff could be operating lorries while under the influence of drink or drugs.
An internal audit on HGV safety was ordered after 11-year-old Thomas Wong was killed by a non-council bin lorry in Barnton in February.
The report has recommended alcohol and drug testing for drivers after managers said they were not able to act over “suspected behaviours”.
Previous plans for substance testing, which are not supported by trade unions, were rejected by city councillors last year as “invasive and unnecessary”.
City of Edinburgh Council’s fleet and operational services managers are currently asked to observe and record any suspected drink or drug use.
They are required to send colleagues home or involve HR or police when they “reasonably believe” that a staff member is under the influence.
But the report stated: “Audit discussions with the council’s fleet and operational services highlighted strong concerns around the potential use of alcohol or drugs while driving for the council.
It added: “Managers expressed reservations to allege colleagues for alcohol/drugs consumption at work, based only on suspected behaviours, and they are unable to take concrete actions where the concerned colleagues deny the consumption.”
The council’s current drugs and alcohol policy was agreed in May last year.
Testing for substances was deemed unnecessary in an amendment tabled by the Greens and supported by Labour, SNP and Lib Dems councillors.
But the council’s Conservative group leader, Iain Whyte, said any accident involving an HGV resulting from a driver under the influence would be “catastrophic”.
He said: “The audit shows that this policy needs to be changed as soon as possible.
“People who drive on council business should be checked to ensure they are safe, not just for their benefit but critically to protect the public.”
The audit came after Thomas Wong died after being struck by a bin lorry while riding his bike on Whitehouse Road. His family said they were “utterly heartbroken”.
Thomas was the second child killed by a bin lorry in a single week after 11-year-old Elizabeth Bell died in the Scottish Borders.
Edinburgh council leader Cammy Day said councillors “need to act” if there was evidence to suggest anyone was under the influence at work.
However, he questioned if there were “other ways to respond” rather than random drug and alcohol testing.
Cllr Day suggested that could include stricter enforcement of existing policies for managing staff absences and managing people at work.
He added: “There should be an option to look at all these things to make sure that our staff are safe and that if they’re driving council vehicles we are confident in ensuring the public are safe as well.”