On the left, while supporting equal opportunities, there'd be simply no reason to support outcasting individuals, especially when many ex-cons were raised in poverty and are URM. You don't have to be like SFiscans(tax breaks for employers that hire ex-cons) to be against this.

but as someone on the left, a great deal of what is taken for granted in the US penal system is categorically unacceptable to me. In my country (Ireland) and most other EU countries except the UK, people in prison are still allowed to vote in elections, for example; we consider the ideal of political self-determination so sacred that it is inalienable even if you lose your liberty.

Of course a cynical rejoinder to this is to point out the futility of voting as a political determinant and I can't really answer that other than to stand on principle. As a pragmatic matter I dunno how you expect people to reintegrate into society by formally excluding them from the annual rituals of civic participation but then most hardliners aren't interested in the rehabilitation arguments anyway. As a foreigner living in the US I can't vote anyway and I feel left out on election days; I think eliminating the franchise for people with a felony conviction is an appalling psychic injury to inflict on people (even if they never voted before going into prison) and it's one of the least defensible features of UK and US culture.

As someone on the right, one issue here is who is doing the restricting of freedom. One approach that strikes me as reasonable is requiring full disclosure, but the state then can't interfere in the relationship between a business and potential employee, aside from obvious exceptions like crimes of pedophilia and care of children.

In between there can be issues where someone is put in a position of trust over other's lives, like, say, a bus driver. But this sort of meat ax approach ... no, I doubt it's going to find a lot of support on the right. Certainly not from myself.