A Labour peer who sent and received text messages minutes before he was involved in a fatal crash on the M1 has been jailed for 12 weeks.
Lord Ahmed, 51, was driving his Jaguar when he hit a stationary car in the outside lane of the motorway - Martyn Gombar, 28, was killed.
Lord Ahmed, of Rotherham, had admitted driving dangerously.
Mr Justice Wilkie said: "It's clear the dangerous driving had no causal link to the accident."
The peer also faces expulsion from the Labour Party following his jail sentence.
A Labour Party spokesman said: "The Labour Party does not comment on individual cases, but under the party's rules any member who receives a custodial sentence is subject to automatic exclusion."
The crash happened near junction 35 of the southbound carriageway at Rotherham on Christmas Day 2007.
Mr Gombar, who was Slovakian, was living in Leigh, Greater Manchester, at the time of his death.
He had crashed into the central reservation, leaving his Audi facing the wrong way in the third lane of the motorway.
One motorist had already clipped his car and another had to take evasive action to avoid it.
The court had heard how Lord Ahmed sent and received a series of five text messages while driving in the dark at speeds of, and above, 60mph along a 17-mile stretch of the motorway.
Mr Justice Wilkie made clear the texting incident had no bearing on the fatal collision.
But he added: "It is of the greatest importance that people realise what a serious offence dangerous driving of this type is.
"I have come to the conclusion that by reason of the prolonged, deliberate, repeated and highly dangerous driving for which you have pleaded guilty, only an immediate custodial sentence can be justified."
Earlier, Jeremy Baker QC, defending Lord Ahmed, put a series of points of mitigation to the judge including the peer's years of service to the community and the country.
The barrister also pointed to Lord Ahmed's attempts to help Mr Gombar and how he took it upon himself to warn other motorists about the incident at some personal risk to himself.
Lord Ahmed will serve half of his sentence in jail and half on licence. He was also banned from driving for a year and ordered to pay £500 prosecution costs.
Outside court Lord Ahmed's solicitor, Steve Smith, said he thought his client had been used as a "scapegoat" by those attempting to drive home the message about not using a mobile phone while at the wheel.
He said he was launching an immediate appeal against the sentence.
He said: "I've been with him. He's very philosophical. He's approaching it with great dignity."
Members of Mr Gombar's family said they were not happy with the sentence.
His cousin, David Cicak, said he was hoping for a long prison term.
"He could be out in six weeks, that's nothing."
Lord Ahmed's barrister Jeremy Baker QC, described how the defendant came to Britain as a child speaking no English but built up a successful business and political career before he was made a life peer.
The barrister said his client provided an important function for the country both nationally and internationally, particularly in the field of inter-faith relations.