Assume that you have the ability to travel either forward or back in time up to 100 years. (This is a hard limit.)
Now, it turns out that it is possible to make small changes in history. Many people live out their lives, never impacting the larger course of events to any degree that matters. But due to constraints that I do not pretend to understand, it is inherently impossible to make large changes–so don’t try to kill Hitler, because you’ll simply be wasting your time.
This means that you can, for example, travel back in time and rob a bank. While such an event may have a large impact on the people who actually experience it, it is extremely unlikely to have wide-spread ramifications. You can also travel forward in time and rob a bank, although you’ll be taking a gamble because you have no idea what security measures banks of the future may have.
So you can go either backwards or forwards and commit any crime you wish. (If you go back, and the crime would somehow alter history to any significant degree, something will happen to somehow prevent you from completing it.)
Would you go forward, or back? If you go forward and return successfully, obviously you can’t be arrested for a crime that you haven’t yet committed. On the other hand, security measures may be more effective in the future. If you go back, most statutes of limitations will have expired by the time you return.