If on a sliding scale "conviction" is a 100 and "accusation" is a 20, "arrested" falls somewhere between 18 and 22.

Unfortunately there really is no middle ground. You can't point to an event and say that you're __% certain that the accusation is true. So again it boils down to whether you base the decision off of accusations or convictions alone.

As someone stated elsewhere it's not just an ethical decision, either. Economics should play at least a minor role in the decision-making process.

That's not really in the middle. The only difference between "accused" and "arrested" is that the accuser told the police.

Yes the accuser told the police, and the police thought there was suffecient reason to arrest the accused. That's the important difference. Sometimes the police are told, and they interview the accused and don't arrest them. Sometimes they do. The police are (in theory) supposed to have standards for who they arrest.

In the experience of my friends with regards to sexual assaults in North America, there's a substantial gap between 'accuser told the police' and 'arrested'. I can't imagine it would be any closer of a gap in India.

Is it? I was accused of a robbery when i was a teenager. I was arrested on another kids claim that i had broken into his garage. No supporting evidence, no other testimony. The charges were dropped, but I was cuffed and taken in.

No it's not. Arrests can happen for only an accusation, or even less in some cases.