Concept
The Diligence Duty
Exercising diligence and care
Diligence and Professional Care
The Diligence Duty
Rule 1.3 states the duty in a single sentence: "A lawyer shall act with reasonable diligence and promptness in representing a client."1 The two nouns do different work. Diligence is persistence, the steady effort a matter demands from the day the lawyer accepts it until the work is done. Promptness is timing, the requirement that the effort arrive while it can still help the client. A lawyer can satisfy one and fail the other. One may work hard in a late burst after the opportunity has passed, and another may start quickly and then let the file drift. Both have fallen short of the rule.
The duty also differs from competence. Competence asks what the lawyer knows and can do. Rule 1.3 asks whether the lawyer actually does the work, and does it on time. A lawyer who knows the governing law perfectly can still fail a client by leaving the file untouched. The rule's text does not make the duty depend on a missed deadline or a lost claim. It regulates the lawyer's conduct, and the harm that conduct causes is a separate question.
The word "reasonable" sets the measure. Matters differ in urgency and complexity, so a looming filing deadline calls for a different pace than an open-ended estate plan, and a contested commercial dispute takes longer to prepare than a routine collection. The standard is therefore objective. It asks how a prudent lawyer would handle a comparable matter. It does not ask how hard this lawyer felt like working or how fast the client hoped the work would move, and it does not demand the most that any lawyer could conceivably do. How far a lawyer's energy may properly go is a separate question, taken up in the discussion of zeal.
The duty runs to the client, so a lawyer must know who the client is before asking what the duty requires. Diligence, communication, and confidentiality are all owed to the client.2 Elder law practice shows the point. When an adult child brings a parent to the lawyer's office, the parent is generally the client, because it is the parent's situation that is being addressed. The lawyer owes the parent timely, persistent work. A relative who attends the meeting or pays the fee does not become the client on that fact alone.
A client cannot easily watch the pace of legal work, and that is why the duty matters. Many legal rights are perishable, because limitations periods and filing deadlines expire whether or not anyone is paying attention. From the client's side, an idle file looks exactly like a file being worked in the background, and the first visible sign of trouble may arrive only after the opportunity is gone. The client has handed the pace of the matter to the lawyer, so reasonable diligence and promptness are what the client is relying on.
The pair isolates the fact that decides the case. Calendar time does not separate the lawyers, since the second matter also took weeks, and it is not whether a deadline has yet been missed. What separates them is whether each lawyer's work tracked what a prudent lawyer would do for that matter. For that reason the first lawyer can violate the rule while the claim is still alive. The unreasonable delay is the breach. Any harm that follows, such as a time-barred claim, bears on the later questions of malpractice liability and damages.