The legal system is too complex for your average reporter to understand. They operate at the level of stories rather than systems, rules, allocations of decision making power, etc.

I had a civil procedure professor once explain various federal court procedures in terms of the flow of cases through pipelines, and an evidence professor who explained the rules of evidence in terms of Bayesian statistics. But if you’re smart enough to understand that, you can make a lot more money doing something other than being a reporter.