It is not ethical or professional as provided below via the Canon Of Ethics from the American Bar Assocation - while many states have become lax on advertisement (used to be termed ambulance chasing) of lawyers and firms they still frown on the letter as a form of solicitation as it really is a direct attempt to stir up litigation
Canon 28. Stirring Up Litigation, Directly or Through Agents.6
It is unprofessional for a lawyer to volunteer advice to bring a lawsuit, except in rare cases where ties of blood, relationship or trust make it his duty to do so. Stirring up strife and litigation is not only unprofessional, but it is indictable at common law. It is disreputable to hunt up defects in titles or other causes of action and inform thereof in order to be employed to bring suit or collect judgment, or to breed litigation by seeking out those with claims for personal injuries or those having any other grounds of action in order to secure them as clients, or to employ agents or runners for like purposes, or to pay or reward, directly or indirectly, those who bring or influence the bringing of such cases to his office, or to remunerate policemen, court or prison officials, physicians, hospital attaches or others who may succeed, under the guise of giving disinterested friendly advice, in influencing the criminal, the sick and the injured, the ignorant or other, to seek his professional services. A duty to the public and to the profession devolves upon every member of the Bar having knowledge of such practices upon the part of any practitioner immediately to inform thereof to the end that the offender may be disbarred.
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