Sam Waterston quitting Law & Order feels like losing a TV dad

McCoy is a fundamental part of Law & Order, along with its trademark two-part structure, the shoddy, flimsy false alibis, and the iconic, ever-reverberating dun-dun.

The formula is reliable and well-worn in an ever-changing world, with the cases, so often ripped from headlines, neatly resolved in a one-hour episode – in turn satisfying our longing for simple solutions to hard truths.

My introduction to the character came through re-runs, when he first appeared in the season 5 premiere. It was all there: the swagger and confidence, the unrepentant self-righteousness, the lapses in professionalism, the McCoy coolness.

But he's mellowed since, as we all have, going on to become the face and steady presence of Law & Order.

One of the show's and McCoy's most important moments occurs in season 6's Aftershock, when he witnesses an execution. What follows is a thoughtful, subdued discussion about the moral complexities of capital punishment, which humanises him and the issue itself, proving that the best, most impactful television happens in its quieter moments.

My own favourite McCoy moment happens during his cross-examination of a defendant in season 15's Fluency, when he uses a poignant analogy from an Orson Welles film to cut through his excuses.

The man claims he couldn't have known that distributing counterfeit vaccines would lead to 16 people's deaths, but McCoy's response shatters his lies by cleverly exposing his apparent indifference to the dead: "And you couldn't foresee the risk to those patients? They were just dots to you, weren't they? Far away, insignificant. And if they suddenly stopped moving, who'd care? Not you!"

McCoy has a knack for dragging the jury and the audience along with him, and making them truly care, also.

We often become numb to the issues that are explored on screen, but McCoy has a way of engaging a viewer. He is, beyond all of his talents, an ordinary, imperfect man at his core, often encouraging us to trust our gut. McCoy is law bound up in passion and emotion, an infectious trait that draws us in further.

That approach is on display in 1994's Virtue, in which he passionately defends a victim of sexual coercion. At a time when women and girls continue to be failed by the criminal justice system, his words still feel progressive, designed both then and now to make the audience think, to drag them out of their detachment numbness.

"Sarah Maslin worked," he said. "For eight years, she was the best, the most productive associate in her firm. She had clearly earned a partnership. But the only way that she could get it was to have sex with a man who had the power to make or break her career. Sarah Maslin laid down on that couch for Mr Talbert. But can any of us say that she really had a choice?"

Amid all his legal prowess, the raw authenticity of his human response to the many victims and cases that coloured his career stands out, as we see in Gunshow, when he empties a box of bullets onto the courtroom table while prosecuting a gun manufacturer.

The sound chillingly reverberates as each one strikes the wood, just as they would victims.

Of course, the character is an ideal, and since its creation, Law & Order has arguably offered a sanitised view of police work and built stories based on false narratives about the fairness of the criminal justice system.

The police will find a suspect; the district attorney will convict them without bias or prejudice. Case closed.

That's a key part of why we become so attached to is characters: the emotional connection, the ease, the continuity and the familiarity they provide.

Counsellor Georgina Sturmer puts it this way: "TV programmes elicit an emotional response from us, in the same way as stories about people in real life. We build emotional bonds and feel the whole range of human emotions."

It also gives us a place to direct our own emotions, a catharsis of sorts. "TV programmes allow us to connect with feelings that we might ignore or suppress in real life. This all explains why we can feel a genuine sense of connection to our TV family," she adds.

That is absolutely true of McCoy.

Saying goodbye to him was never going to be easy; he's become something of a mentor, a role model and a blueprint for life. In a world where we all need something to believe in, I had McCoy.

But at least we'll always have the reruns, as Waterston noted upon the show's earlier return: "It's nice to come back and just witness the thing we made."

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