By Phil Mackie
BBC News, Warwickshire
There were times this morning when the M6 in Warwickshire resembled a car park.
There were not any accidents, but the volume of traffic and the heavy rain meant that, at times, it came to a complete standstill.
It was just the type of situation when motorists might be tempted to make a phone call, either to warn people that they would be late for an appointment or an important meeting, or simply to relieve the boredom.
This was not the day to use the mobile.
Will drivers think twice about using the phones?
Warwickshire police patrol cars were out in force, cruising along the motorways and major roads looking to enforce the new law.
After two years being frustrated by the lack of impact from the £30 fines, they now feel the law suddenly has teeth.
The maximum fixed penalty fine has now doubled to £60, and three points can be added to offenders' licences.
Chief Inspector Adrian Knight was running the operation.
"People took it on the chin, and were quite happy to pay it," he said. "But now with the endorsements people are thinking twice about using the phone."
There was a steady stream of drivers being stopped, ordered to pay the £60 fine, and more importantly having three points put on their licence.
After three hours the number of endorsements had reached 30.
Not surprisingly, the drivers were not happy.
Roger Mole, from Sandwell in the West Midlands, fell foul of the regulations even though he had his hands-free set plugged in.
He received a text while he was driving, and clicked on it to see who it was from. Unfortunately for him, as he did so, a patrol car was driving past.
"And the next thing I knew I had the police pulling me over," Mr Mole said. "I didn't think I was going to get booked... I said, 'can't you just give me a warning?'"
The answer was "no".
And it was "no" to the woman who tried to convince officers that she was hands-free because she was cradling the headset between her shoulder and head as she was driving and holding a conversation.
A HGV driver who had been spotted speaking on his phone said he would contest the endorsement and that he would see the police in court.
He denied being at the wheel while speaking on the phone.
But he also took the precaution of deleting all his recent calls from the phone while the officers were speaking to him.
However, many drivers simply put their hands up and accepted their fate.
A 24-year-old burst into tears when the police caught him speaking to his girlfriend as he drove along the motorway.
Ironically, he had just been listening to a radio report about the changes in the law.
One of the police officers handing out the tickets was Pc Paul Keeling. He doubles up as a family liaison officer.
He said that detectives were not simply using their new powers to harass motorists - but using an important new tool to try to make the roads safer.
He said: "Part of my job is to go round and explain to families that a loved one is dead, and 'by the way I need someone to come down and identify their loved one at the mortuary'.
"People just do not think... that's the problem, they don't think"