For example, a $200 speeding ticket is more devastating to a 20-year old college student who works part time than to someone with a well established career. The college student would be straddled with a comparatively heavy, unexpected, and stressful punishment, whereas the worst thing about the fine to the person with a good career would be the minor annoyance having to go to the courthouse to pay it. Those with enough money could knowingly and repeatedly break the law simply because they can afford the costs of re offending.
Fines should be replaced with a system where certain crimes are worth a percentage of your annual income. The government already has access to your tax records, all it would take is some interdepartmental communication. With computers, the calculations would be done almost instantly with a Social Insurance Number and photo ID. If you're below a certain income threshold, then the fee can be made up by community service or something. That way, everyone is punished as equally as possible.
Income level shouldn't affect a jail sentence because time affects everyone at the same rate.
1) For higher fines when one has to appear in court the prosecuting attorneys already take this into account. If you tell them you are a struggling mother of 3 they will typically take it easier on you than some rich kid. In my state this applied to most traffic violations where points are involved.
2) How could you enforce this? Income isn't a great predictor of wealth. If I make 200k in NYC and have 4 kids then there won't be much funds left to pay steeper tickets. The law can't take into account all these factors so keep it simple.
It is hard to enforce such a system in real life. On paper, it sounds legit. But take into account of the possible consequences. Can the argument be stretched to say that the rich should be in jail longer for the same offence just because being in jail longer affects the livelihood of the poor more than the rich? Also, how will the judge decide how much to fine for each individual? Everyone's income is different. Granted, they can create different fines for different income groups to make it easier. But ultimately we have to weigh whether it's worth the hassle to go to such an extent, given that it's the government's resources we're using.
I do not disagree that this should be applied in certain cases. Cases such as where the offender shows no sign of remorse and is likely to be a repeat offender. By all means, slap them with a heavier fine if they're rich. But these cases should be up to the judge's discretion and not “normalised" such that it's applicable to all of the rich. I do not feel that there is any significant problem right now that warrants the introduction of such a phenomenal change in the legal system.