The main thing about Jeremy Renner is a sense of integrity, and that’s just what you want in a movie like Kill the Messenger, not least because there already are lots of movies like Kill the Messenger. It’s another more or less true story of a more or less stand-up guy sussing out corruption and, well, standing up to it. But there’s something special about Renner in the role of the late Gary Webb, the San Jose Mercury News reporter who paid dearly for writing about how the CIA-supported war in Nicaragua begat America’s crack epidemic. Marshaling the brisk intensity that has served him well on Homeland, director Michael Cuesta delivers a cleanly distilled, soberly conventional political conspiracy thriller, anchored by a guy who loved motorcycles and his family, wanted his work to matter, and was out of his depths when suddenly it did — but then who wouldn’t be? “Dark Alliance,” as Webb’s investigative series and later book was called, proved to be the high point, and the end, of his career. In Cuesta’s presentation, Rosemarie DeWitt nicely humanizes a stakes-signifier role as Webb’s wife, and Ray Liotta gets a juicy cameo. But the best thing about this ultimately very depressing story is the final vindication to be had by Renner’s commanding presence in it.