Despite what the majority of site reviews here seem to indicate, The Shield for PC is actually a fairly decent game. My deep-seated suspicion is that many of these sites sent both versions of this title to reviewers (PS2 and PC) and most reviewers probably reviewed the console version first since it seems to be a title more fitting for a console than a PC. However, the PS2 version is known to be genuinely crappy and after playing a crappy game on one system, it's very likely that quite a few of these reviewers never even bothered to play through the PC version and just mailed in their reviews for that platform.
Having played the game, I can say that it definitely had some enjoyable elements (shooting, foot-chases, torturing suspects) and had excellent voice-acting (the entire case, virtually, did their own voices), while mostly capturing the feel of the series. Yes, there were issues (some desktop crashes, average-looking textures, and at times, overly simplistic gameplay) but for the low price of the game and the fact that the game DOES capture the feel of the series, I believe it deserved a much better score than some of the review sites would have you believe. Like I mentioned above, I'd bet good money that most of the reviewers who supposedly reviewed this game, did not, in fact, actually review the entire game, if any of it.