A COACH driver could face criminal charges following the death of schoolgirl Natasha Paton after an inquiry ruled he was driving too fast in wintry conditions at the time of the fatal crash.

Natasha, 17, was on a school trip to Alton Towers when the bus hit Castledyke Bridge, near Biggar, on March 31, 2010, throwing her through the coach window and into a freezing burn.

In her determination Sheriff Nikola Stewart ruled the accident was caused by driver Raymond Munro losing control of the coach at a sharp bend due to excessive speed and poor weather which made the road slippery.

She also found the death of the sixth-year student at Lanark Grammar School, might have been avoided if she and other passengers had worn seatbelts as their teacher told them to.

The Crown Office and Natasha's parents now want seatbelts similar to those in cars for public transport to be considered, with a system to detect those not wearing them.

The Fatal Accident Inquiry found Mr Munro, who did not give evidence due to ill health, approached the narrow bridge at at least 23mph and braked while negotiating the tight turn.

It was dark with snow falling increasingly heavily.

The determination said: "The crash and the resultant death of Natasha might have been avoided had the approach to and turn on to Castledyke Bridge been taken at a slower speed by the coach driver.

"The speed at which the bend onto the bridge was approached and taken was excessive given the prevailing weather conditions and increased the risk of loss of control of the vehicle, and reduced the opportunities available to the driver to take steps to avoid or successfully respond to any skidding -

"Had the driver taken steps to reduce his speed to an appropriate level prior to negotiating the sharp turn on to the bridge, the loss of control which occurred could have been avoided or ameliorated."

The Crown Office said it would give the determination careful consideration.

David Wilson, solicitor for Natasha's parents Jacqui and Gordon, said: "The loss of Natasha has devastated her family. It is however some comfort to them that this inquiry has clearly established that Natasha Paton's death was caused by Raymond Munro - Had Mr Munro driven with reasonable care, the accident would not have happened."

In her determination, Sheriff Stewart praised the "admirable fortitude" of staff and students after the crash and noted scenes of chaos as teachers tried to free more than 30 pupils by removing the front windscreen of the coach.Mr Munro was also rescued.

Natasha died from drowning within minutes of the crash, her body was found in water around 40 minutes after the accident.

The determination said: "It seems likely Natasha was ejected from her seat and thrown out of the adjacent window as the bus fell sideways through the descent from the bridge. She was not wearing a seatbelt and nor were some of the passengers seated nearby who were therefore unrestrained from falling against her.

"The window glass had shattered due to the forces at work in the collision and fall, offering no resistance to her passage. Had she been wearing a seatbelt she is likely to have been restrained within her seat. No other injury sustained by her was life-threatening."

Pupils had been told by teacher Ross Allan to put on seat belts, and two checks were carried out to ensure they complied.

The FAI found around 12 passengers were not wearing seat belts at the time of the crash, with four of them sitting close to Natasha.

Sheriff Stewart added: "No criticism can be made of the attempts made by teachers to ensure the wearing of seatbelts."