The Tax Collector is the second-best David Ayer-directed film (the best remains End of Watch), but it's far from the best David Ayers-penned movie – though to be fair, that includes Training Day and Dark Blue, as well as the aforementioned End of Watch.
The script can be nicely subtle, especially when it comes to the character of Creeper (Shia LaBeouf putting his natural weirdness to good use); he's always impeccably dressed in a suit and tie, but his cauliflower ears are a dead giveaway – here's someone who can take punishment as well as dish it out.
This is great stuff, but at some point you gotta put your money where your mouth is, and that's where the character shortchange us. Much is made of how Creeper has maimed, tortured, and murdered hundreds of people, but in the course of the film he only fires his gun once, and then in self-defense; on the other hand, he's given a martyr's death, but I'm not sure whether we're supposed to feel bad for him or not. If all that's said of him is true, he has it coming to him; if not, we've been fed a line of bullsh*t.
Having said that, the script can also be painfully unsubtle, in particular when it's trying to convince us that the protagonist, David Cuevas (Bobby Soto), is a Killer with a Heart of Gold (talk about a crock of sh*t) – a family man who prays before every meal and advises Creeper to accept Christ in his heart, as opposed to antagonist Conejo (José Martín), who engages in human sacrifices and voodoo rituals.
That's pretty black-and-white, when it should be shades-of-gray; in other words, The Tax Collector's problem is that it insists on splitting its characters into 'bad guys' and 'good guys' when 'bad guys' and 'worse guys' would be a more accurate division.