Council policy requires windows in private hire cars and hackney carriages to have “light transmission” rates of at least 75 per cent in the windscreen, 70 per cent in the front side windows and 34 per cent elsewhere.
A report by the council's principal licensing officer Suzanne Fisher and public protection manager Anita Hunt said they had received two written requests to review the policy.
One of these said it was “expensive” for drivers to conform, and “many drivers are moving to Shropshire Council or [City of] Wolverhampton Council as a result”.
A petition also argued darker back windows “reduce the risk of small children and babies suffering sunstroke”.
Ms Hunt told the borough’s Licensing Committee that they discussed standards with neighbouring councils, but each was free to make its own rules.
As well as specifying light transmission rates, Telford and Wrekin’s current rules also mandate that registered taxis cannot have windows darker than those offered as a “factory-fitted option” at the time the car was made, Ms Hunt said.
They also need to be “constructed so as to enable passengers to be seen in the vehicle from all directions when observed from outside”, she added.
She said the rules were introduced in 2017 for a range of public safety reasons, including ensuring drivers were not carrying excessive numbers of passengers and discouraging illegal, dangerous or suspicious activity inside.
“Passengers need to be able to see who is in the vehicle before they get in, and vulnerable passengers, such as lone females and young persons, will feel safer in the vehicle where they can be seen,” she added.
Councillor Jacqui Seymour asked whether Telford and Wrekin Council could persuade neighbouring authorities to “fall in line with the standards we set”.
Ms Hunt said: “We do, obviously, discuss matters with neighbouring councils, but it is their decision if they want to adopt our standards.”
Councillor Jim Lavery asked about the standards in Wolverhampton, and Ms Fisher told him: “Wolverhampton just allow factory-fitted tints, so you will see vehicles licensed by Wolverhampton working in Telford with not just dark tints but ‘privacy windows’, where those have been fitted at the point of manufacture.”
She added there was no law governing the darkness of windows in private hire cars specifically.
New government-issued taxi standards will be discussed by the committee at a future meeting, but Ms Fisher said these also contained “no mention” of tint levels.
During a consultation period leading up to this week’s meeting, a 139-name petition, submitted on behalf of Diamond Cars and Go Carz, asked the council to “remove the percentage of light transmittance permitted in licensed vehicles from the existing licence condition”, leaving “no specification to the level of tint permitted other than the windows being required to be factory fitted at the time of manufacture”.
Ms Fisher and Ms Hunt wrote: “The reasons given for this are that it will reduce the risk of small children and babies suffering sunstroke and it will reduce exhaust emissions by reducing the need to open windows or use air conditioning.”
The committee voted unanimously to maintain the current system.