Yes, autism is a spectrum disorder and it manifests itself in different ways. However, taking your advice, Google reveals to me (as I suspected) that the majority of those with autism know the difference between right and wrong (moral reasoning), often quite strongly. As do people with depression.
Admittedly I'm on the slant of those that think that everyone seems to have an excuse for everything these days - and don't take responsibility for their own actions.
*This is of course not a slight against those with autism or depression.
*And, innocent until proven guilty, as others have said.
Have I covered off on all the PC ****e I needed to?