He's a monster, but the policy against conjugal visits is monstrous, too. We take enough humanity from the men and women who spend time in prison. If one of them has a wife or husband or is in (fucked up, hopeless, crazy) love, I see no reason why private visits between the two should be banned.

For people who argue that forcing couples apart from each other bodily is morally permissible, let me ask you this: do you consider intimate connection a necessary part of most romantic relationships?

If not, then we probably can't come to an agreement. But if so, you have to provide a positive moral worth that outweighs the moral detriment of separating such couples as a general rule (because mutual love between two people is something that should not be interfered with unless one can prove banning interactions based upon particular traits as a general rule is of benefit to humanity.)

I would argue there is no such moral counterweight to the stifling of love that the policy of no conjugal visits creates. One might say that putting prisoners in such a situation would make them less likely to return to crime because they have seen the consequences of their misdeeds--but prison anywhere in the world already does that job quite thoroughly for anyone who is receptive to the message. One might say that some prisoners do not deserve love--but love is the most healing and redemptory force in existence, and romantic love requires occasional physical connection for most people. I can't cite a source on the claim that prisoners who get married in prison are less likely to re-offend, but that seems pretty likely, right? They have more to lose once they get out, and something to look forward to keeping while they're still in prison.

And then there's the whole problem with punishing the man or woman a prisoner has fallen in love with by taking away a necessary element of a romantic relationship. They did nothing, except somehow fall in love with someone who is incarcerated.

Lastly, we all know the "jokes" about prison rape. You can draw your own conclusions about what an across-the-board policy permitting conjugal visits from outside the prison might do to the epidemic of rapes between prisoners. (Personally, I think there's no way it would be enough to totally eliminate it, but it would probably reduce it.)

TL;DR, policies against conjugal visits in prison are inhumane and counterproductive.