Philadelphia lawyer: an especially shrewd or competent lawyer, knowledgeable about legal technicalities, maybe a little unscrupulous

The term Philadelphia lawyer is first cited in the late eighteenth century, often in the phrase "It would puzzle a Philadelphia lawyer." By the early 1900s, the term had pretty much died out. The original Philly lawyer is rumored to have been one Andrew Hamilton, who successfully defended his client against libel charges in a widely known 1735 court case. However, Philadelphia was well supplied with famous lawyers in the late eighteenth century. Twenty-six of the fifty-six delegates who gathered there to sign the Declaration of Independence were members of the legal profession.