FMD had few compunctions about 'criminality' as most people describe it. While there are no grounds to describe him or his literature as a proponent of criminal behaviour, he clearly and repeatedly expands on the criminal as a necessary type whose socially divergent behaviour leads to suffering and, ultimately, redemption. In "House of the Dead," he asserts that prison is occupied by just as many 'good' and 'bad' people as anywhere else in the world.
Throughout his books, FMD makes mention of two criminal variants who, while they may not be 'beyond' redemption, are baser than the more garden variety thieves and murderers who he describes at some length elsewhere. One of these types is mentioned in "House Of The Dead." He is one of a small handful of 'upper class' prisoners (among whom the narrator and Dostoevsky himself also numbered) who are alienated from the rest of the prison population by virtue of their genteel backgrounds. This man is described as a former state official, an ex-employee of the Third Department. During his career, he committed numerous acts of perjury and falsely incriminated many individuals, resulting in lengthy prison stays and ruined lives for many of these people. According to the narrator, this particular person doesn't have a single redeeming quality; he's slothful, devious, cunning, malicious, etc.
I associate this type with the modern idea of the 'white collar criminal,' someone who uses a position of legitimacy to illicitly divest others of money or other resources. For a good while, I chalked Dostoevsky's bias towards this type as the sensible conclusion of a poor man who had been unduly taken advantage of himself by a corrupt state. To him, this man probably embodied the enigmatic, corrupt apparatus which accused Dostoevsky of sedition and ruined his life. One doesn't get the impression that this is meant to be a philosophical maxim so much as a personal polemic, basically. I doubt that a more affluent writer...Tolstoy, say, or for that matter just about any of Dostoevsky's contemporaries...would have singled out this type as particularly reprehensible, certainly not 'more so' than, say, a man who murders a dozen people in cold blood.
The second sort is a lot more ubiquitous, though. I'm referring to the Stavrogin type, which appears repeatedly in Dostoevsky's later work. Specifically, the worst type of criminal was someone who 'prevents someone else from being able to love.' Stavrogin's rape of a child was the ultimate embodiment of this, but the idea is recurrent...Svidrigailov, Prince Valkovsky, Totsky, Murin, etc. The effect that these people have on other characters in the books is incomparably egregious because their actions produce a feeling of anhedonia; unfeeling, 'death in life.' To me, this idea represents depression, an ultimate inability to accord life any sort of potential. It would have been 'better,' from Dostoevsky's point of view, had such people killed their victims outright instead of reducing them to what is pretty well a literal form of hell on earth.