This isn't a new phenomena, and the most famous lawyer's apprentice was probably Abraham Lincoln. "Before the prevalence of law schools in the 1870s, apprenticeships were the primary way to become a lawyer." And there is still "[a]n obscure California rule that allows people to 'read law' much as Lincoln did, studying at the elbow of a seasoned lawyer."
California is not the only state that still allows people to read the law. "California is one of a handful of states that allow apprenticeships in lieu of a law degree as a prerequisite to taking the bar and practicing as a licensed lawyer. In Virginia, Vermont, Washington and California, aspiring lawyers can study for the bar without ever setting foot into or paying a law school. New York, Maine and Wyoming require a combination of law school and apprenticeship."
The more popular route, today, is to attend law school as state bars generally require a J.D. from an ABA accredited institution as a prerequisite to taking the bar. "The [apprenticeship] programs remain underpopulated. Of the 83,986 people who took state or multistate bar exams last year, according to the National Conference of Bar Examiners, only 60 were law office readers (so-called for the practice of reading legal texts as preparation)."
As noted, "there are obstacles. None of the states help prospective law readers locate a supervising lawyer, and finding one willing to take on the responsibility of educating a new lawyer can be difficult (supervising lawyers are expected to instruct their students in all areas of law covered by their state’s bar exam, and administer and grade tests). Bar passage rates for law office students are also dismal. Last year only 17 passed — or 28 percent, compared with 73 percent for students who attended schools approved by the American Bar Association."
But as the cost of law school continues to rise, this might be an alternative for someone really looking to serve the community without the staggering debt that often accompanies a law degree. As one lawyer's apprentice in California noted, "[t]here is very little that would entice me to go $100,000 or more into debt for a credential."