I think anyone familiar with Alan Clarke's Scum who then watches Rick Rosenthal's Bad Boys will notice some striking similarities between the two films, in narrative, thematic, and visual terms. To me, there are enough parallels that Rosenthal and Bad Boys screenwriter Richard Di Lello (author of The Longest Cocktail Party) probably should have given some direct acknowledgment to Clarke and writer Roy Minton's film (as well as the earlier Scum teleplay that proved to be too much for the BBC).
Bad Boys is a pretty rough film, particularly for a mainstream American product intended largely for teen audiences. Scum, however, makes its American cousin look like a preschool picnic and is a much stronger film for it. Where Bad Boys injects a love story into its narrative, an inspiring, incessant Bill Conti score, a Rocky-like final fight, and a theme of redemption, Scum doesn't attempt any of these softening, conventional touches.
What the American film hints at or suggests, such as male-on-male rape, Scum pulls no punches with and rubs the viewer's nose in. There are mostly sympathetic guards and administrators in the juvenile prison where Bad Boys star Sean Penn does time; the men who run the borstal in Scum range from cold and unfeeling to unrepentant sadists.
In Bad Boys, the prison is shown to be flawed, but the film still makes it a force which turns bad boy Penn into a better man. The borstal in Scum is a brutal, inhumane place and the film offers no hope for those inside or for some kind of reform to the system. A few years after Scum was released, the borstal system was abandoned in the U.K. Whether the film influenced this in any way and how truthful the film is to the actual borstal experience, I'm not certain.
EDIT: I just found out about a French-Canadian remake of Scum, entitled Dog Pound, via this most informative Scum Wiki page.