Have always found a lot to like about all three of the three best known and popular 'Law and Order' shows (the original 'Law and Order', 'Special Victims Unit' and 'Criminal Intent', the others are more variable). Although 'Special Victims Unit', great in the earlier seasons but less consistent in the latter ones, has topped the original as the longest-running of the franchise in terms of seasons, my personal favourite is the original, if more the Briscoe years and before.
"Tombstone", actually a first part to a two parter (which concluded on the very short lived 'Law and Order: Trial by Jury'), to me is a great episode. A strong contender for the best one of the second half of Season 15, the best since "Gunplay" and the last one of the season to be great (was mixed on the next four). It may not be 'Law and Order' firing on all cylinders, but as far as Season 15 goes, "Tombstone" is one of the better episodes.
A bit routine to begin with, but it very quickly becomes a lot twistier and more intricate.
Photography while very close up doesn't come over as too static or filmed play-like, while the production values are typically solid and have subtle atmosphere while not being drab and keeping things simple. When the music is used it is haunting and has a melancholic edge that is not overdone. The episode is sympathetically yet uncompromisingly directed. The acting is very good, Jesse L Martin and Fritz Weaver particularly (do agree that Annie Parrisse has settled very well and is a big improvement over Elisabeth Rohm).
It is an intelligently and tautly scripted episode, especially when in court and the hard boiled banter between the detectives. The story becomes increasingly intricate and twisty, without feeling rushed or convoluted, and there is genuine tension as the conflict mounts. The ending did shock me on first viewing and it still does have the shock factor, the abruptness of the resolve didn't sit right with me at first as it was not clear to me whether it would continue in another episode. It does luckily, but it does mean having to watch another show to see the conclusion. Not my favourite kind of ending, incompleteness is a danger, but executed well here and makes one want to see the episode concluding the story (it's concluded on 'Trial by Jury').
Overall, great. 9/10.