Note: I am happy to report that the Coalition Government finally listened to concerns expressed by me and many others over this and section 137 came into force in March 2015 as one of that Government's final actions.
In July 2006, Kelly Woodward, died when the car in which she was travelling as a rear seat passenger was driven into a tree. The driver, Andrew Burrell, was convicted of causing her death by dangerous driving and of driving over the alcohol limit. He was sentenced so leniently that the Court of Appeal intervened imposing a 4 1/2 year prison sentence and a 5 year driving ban.
Kelly's family were nonetheless dismayed to discover that much of the ban would pass whilst Burrell was behind bars and they campaigned tirelessly for a change in the law so that a driving ban would start when an offender was released from any prison sentence imposed in respect of the same offence. She handed in a petition to Downing Street (then occupied by Tony Blair) and enlisted the support of Jack Straw (then Lord Chancellor/Justice Secretary).
I understand that Kelly's family were invited to the House of Commons Gallery to watch the passage through Parliament of the Coroners and Justice Act 2009 which received royal assent on 12th November 2009.
Section 137 of that Act provides that Schedule 16 makes provision about the extension of disqualification from driving in certain circumstances. Schedule 16 in turn amends The Road Traffic Offenders Act 1988 by introducing a new "s35A Extension of disqualification where custodial sentence also imposed" which in rather convoluted language provides for the period of disqualification to be increased by (broadly) half the prison term which I take to be the period of imprisonment that the offender could be anticipated to actually serve in prison. (Quite why it does not provide more simply for the period of disqualification to commence on the day of release I do not know but I am not a parliamentary draughtsman, nor even a criminal lawyer).
HOWEVER section 182 of the same Act provides that certain sections come into force when the Act is passed; that certain other provisions come into force 2 months after the passing of the Act; that more other provisions come into force on 1st January 2010; that yet further provisions come into force on such day that the Lord Chancellor may by order appoint and the remaining provisions (including section 137 as it has not been specified elsewhere) come into force on such day as the Secretary of State may by order appoint.
A general election intervened in May 2010 when the Secretary of State had still not appointed a date bringing section 137 into force.
Incidentally the term 'the Secretary of State' under the Interpretation Act 1978 means any one of 'Her Majesty's Principal Secretaries of State' so in practical terms means the Government.
Now five years on, it seems fairly clear that the Government is not going to appoint a date for the coming into force of section 137. This is not self-evidently a party political matter. More likely it is simply a personality matter. Jack Straw backed this law but his influence with government ended in May 2010 and he perhaps had other things on his mind in the dying weeks of the Brown administration.
It does though appear at best unfortunate that a change in the law, hard fought for by Kelly's family, has come to nothing for the want of a Secretary of State's signature on a commencement order.