From my perspective, there are rare instances when a writer creates a fresh character in literature…
I was told while attempting, and failing, to grow up, that if I wanted to be a writer, I had to "experience life," which meant be exposed to a variety of different jobs for background material. I believe this is a valid point, at least from my own experience.
Here's a (partial) compilation of different kinds of work I have performed over the centuries: morning paperboy, corn detasseler, stockboy in California liquor store, shipping department in women's dress factory, rotocast operator in auto parts factory (made arm rests, head rests), Chaplain's Assistant in USAF (Republic of Philippines and Hanscom Field, Massachusetts), bar back in Officers' Club in Germany, grapefruit harvester on Kibbutz Y'fat near Nazareth, Israel, insurance sales (I hated sales), Teaching-Parent in community-based therapeutic group homes in North Carolina, consultant/trainer/evaluator for such group homes, English professor, and professional writer. I have also milked Bulldogs, but that's another story.
Did all those jobs help me become a better writer? Yes, I think they did. Wide exposure to different people, cultures, and countries is a great education. So, yes, I do recommend a variety of experiences for writers. I do NOT recommend milking Bulldogs, however.
I am not even close to being a legal expert, but I have friends who are. On a novel I'm working on (stand-alone, not Thomas O'Shea), I was into my 11th chapter and hit a roadblock. The protagonist reports seeing two men commit a murder. Then he asks the sheriff, "Are you going to arrest them?" And up jumped the roadblock. Could a person be arrested on heresy? If so, then what? When does the District Attorney get involved, would the men be jailed, how much would bail be? And more questions.
So I contacted a friend of mine who's been a county prosecutor and is now a defense attorney. Invited him to lunch and sat down, munched out, and the questions flowed. He cleared up several key details to keep me from sounding like an ignoramus. The novel is not going to be a legal thriller, but I did need to know a few important facts before I could move on. He supplied them, we enjoyed lunch, and he said he'd be glad to help anytime. Roadblocks blown to pieces.
So, let me encourage you writers out there to be sure that the writing ground you're standing on is not shifting sand. Don't hesitate to tap into the expertise of your friends. You might be surprised to see how eager they are to help you. Just don't forget to acknowledge them when you're published.