Exploring the US Judicial System (d3 viz)

This is much too complicated. The path from the federal appellate courts are all the same except for the court of appeals for the federal circuit, so you only need two boxes (and arguably, one) on the bottom.

Same for the states above: one box.

The Supreme Court's original jurisdiction isn't listed on the diagram, e.g., cases between different states.

What would be more interesting would be to look at the data, that is, the number of appeals coming from each box and each state. The S.Ct. only accepts 150 or so cases each year; does looking at the source of these cases teach anything? That is a study that hasn't been undertaken. Is it just a question of population (in which case you'd expect the 9th and the 2nd to predominate) or are there other statistical anomalies. For example, if a third of the S.Ct.'s cases came from the 8th Cir., a relatively small area in terms of population, something must be going on.

I think its not complicated enough.

If your not going to include information on state trial courts, why include the federal trial courts? Most people will step foot in a courtroom, yet most people will not step foot in a courtroom of any court listed in this graph.