Councillor Reid apologised for the lapse in her 'usually high standards'

York City Council installed the system, which changes red lights to green, to help emergency services move through the city's traffic-snarled streets.

Councillor Ann Reid volunteered her daughter's wedding party as a test.

Nine sets of lights were triggered to get her daughter Hannah to the city centre ceremony in August. Ms Reid now admits that was a "misjudgement".

In a public apology, the Liberal Democrat executive member for transport and planning, said she was sorry for the "lapse in my usually high standards".

Heavy traffic

The test run had been a genuine effort to ensure that systems were in place to aid emergency vehicles responding to calls, she added.

She said: "Previous trials of this system had shown that it was difficult to track one car in heavy traffic, which is why it was felt that five cars, which were travelling the route anyway, would be easier to see.

"In hindsight, I do realise now how this could have been misconstrued. For that reason I feel it is unfortunate that I did agree to help."

Ms Reid said that information gleaned from the trial had helped the city engineers conclude that the new system was effective.

The journey from the family home three miles outside York to the wedding venue at the Treasurer's House in the city centre had taken 20 minutes rather than the usual 30 minutes, she added.

'Green wave'

A City of York Council spokeswoman, said: "We've been working on a new system of linking traffic lights to enable emergency vehicles to move around the city as quickly as possible in an emergency.

"It's based on a 'green wave' method, changing all the traffic lights in front of the vehicle to green to give it clear passage.

"This new system has to be tested by following a known, identifiable vehicle or vehicles.

"Ms Reid's wedding party provided a useful opportunity to do this.