A young cyclist who fatally injured a mum-of-two when he collided with her in Old Street has been sentenced to 18 months in a young offenders institution.

Charlie Alliston, then 18, was travelling at between 10 and 14mph on a fixed-gear track bike with no front brake before he hit 44-year-old Kim Briggs in February last year. Riding without a front brake is illegal.

Prosecutors took the unprecedented step of bringing a manslaughter charge against him – of which Old Bailey jurors took more than 12 hours to clear him.

But he was convicted of the lesser offence of causing bodily harm by wanton and furious driving.

The offence, under the 1861 Offences Against the Person Act, carried a maximum sentence of two years in jail.

Sentencing at the Old Bailey Judge Wendy Joseph said: “I am satisfied in some part it was this so-called thrill that motivated you to ride without a front brake shouting and swearing at pedestrians to get out of the way.

“I’ve heard your evidence and I have no doubt that even now you remain obstinately sure of yourself and your own abilities.

“I have no doubt you are wrong in this. You were an accident waiting to happen. The victim could have been any pedestrian. It was in fact Mrs Kim Briggs.”

The judge said Alliston’s “whole manner of driving” caused the accident.

“If you bicycle had a front wheel brake you could have stopped but on this illegal bike you could not and on your evidence, by this stage, you were not even trying to slow or stop.

“You expected her to get out of the way.”

Alliston, now 20, of Bermondsey, raised his eyebrows as the judge told him his sentence would be custodial.

He had blamed Mrs Briggs for the collision. The HR consultant had stepped backwards into the rider’s path and had not been using a pedestrian crossing.

After the crash but before Mrs Briggs died of her injuries, Alliston made a series of social media posts describing how he twice warned Mrs Briggs to “get the f*** outta my way”.

He wrote: “We collided pretty hard, our heads hit together, hers went into the floor and ricocheted into mine.”

He added: “It is her fault but no, she did not deserve it.”

Mrs Briggs’ widower Matthew, from Lewisham, south London, has called for a “radical change” in cycling culture and the introduction of new laws, including causing death by dangerous cycling.

He has said: “I am now determined to do what I can to prevent others from going through the heartache we have had to bear following Kim’s needless death.

“The current law is outdated and has not kept pace with the huge increase in the number of people cycling and the associated increased risk of collisions, nor the attitude of some cyclists.

“We need to change the way the law deals with this.

“I am calling for an introduction of laws of causing death or serious injury by dangerous or careless cycling, thereby bringing cycling laws into line with the Road Traffic Act.”

Reporting by Press Association