Josephson articled at the Nelson law firm of Stewart Enderton, and became notable in 1975 for being named a Provincial Court judge at the age of only 29.
He attended Woodstock College, Galt Collegiate Institute and Osgoode Hall, articling with Osler, Wink & Gwyn.
After his studies, he began articling in the law office of William Buell Richards, but, in 1849, he joined the California Gold Rush.