Barristers will walk out of courts across England and Wales on Monday in a dispute over legal aid funding.
During the strikes, they will not accept new cases or take on work for colleagues whose cases have overrun.
The Criminal Bar Association (CBA) said around 81.5% of its more than 2,000 members who voted in a ballot supported the action.
In a statement released on the first day of action, Mr Raab urged barristers “to agree the proposed 15% pay rise which would see a typical barrister earn around £7,000 more a year”.
However, a spokesperson for the CBA, which represents barristers in England and Wales, said the pay rise would not take effect immediately as it would not apply to backlogged cases.
They said the “record backlog” may mean increased rates were “many years away” for barristers.
As of the end of April, there was a backlog of 58,271 cases, according to HM Courts and Tribunal Service.
Criminal barristers say many prosecutions are being delayed because there is a shortage of advocates to make sure hearings can go ahead.
The number of lawyers working in criminal justice – both barristers who appear before judges in court and solicitors who instruct them – has declined over the last decade, as many say they cannot make a living from the rates paid to them when they take on cases funded by legal aid.
CBA chairman Jo Sidhu QC said that, as well as pay, the strikes are about “redressing the shortfall in the supply of criminal barristers to help deal with the crisis in our courts”.
How much do criminal lawyers earn?
- The Legal Aid rules set limits on fees
- For 13 hours, a solicitor would earn around £250 – an hourly rate of almost £20
- When it comes to court, some barristers say the time they spend preparing cases means their hourly earnings are below minimum wage
- The Law Society has mapped the loss of criminal solicitors nationwide
- In comparison, the website Checkatrade says the average day rate of a plumber is now almost £350 – although there are obviously regional differences
- Lawyers who work in other areas, such as private corporate law, can expect to earn £100,000 a year from very early in their careers.
A shortage of barristers is causing “increasing misery to victims and those accused”, as they are sometimes left waiting years, he said.
He said barristers had suffered an average fall of 28% in their real earnings since 2006 and juniors in their first three years of practice earnt a median income of just £12,200, which is below the minimum wage.
Mr Sidhu said almost 40% of junior criminal barristers left the profession in one year and that more than a quarter of specialist criminal barristers – around 300 – quit in the last five years.
He said: “In reality, our judges have been forced to adjourn 567 trials last year at the last minute because there simply wasn’t a prosecuting or defence barrister available.”
The strikes are intended to span four weeks, starting with walkouts on Monday and Tuesday and increasing by one day each week until a five-day strike from Monday 18 July to Friday 22 July.
Barristers are expected to rally at a number of high-profile courts that manage the most important cases in the country on Monday – including the Old Bailey, Birmingham, Manchester and Bristol Crown Courts.