Is it immoral to put a captcha on a login form?

Question

In a recent project I put a captcha test on a login form, in order to stop possible brute force attacks.

The immediate reaction of other coworkers was a request to remov

Answer 1

I would like to address the question in the title—the question of morality.

I would consider a captcha immoral under the following circumstances:

1. It excludes participation in the application to those with physical or mental challenges, when the main portion and purpose of the application would otherwise not make such an exclusion.

2. The mechanism of the captcha exposes users to distressing language or images beyond what would normally be expected in the application.

3. The captcha mechanism as presented to the user is deceptive or misleading in some way.

A captcha may also be considered immoral if its intent is to exclude genuinely sentient machine intelligences from participation for reasons of prejudice against non-humans. Of course, technology has not yet advanced to the level at which this is an issue, and, further, when it does become an issue, I expect human-excluding gates will be more feasible and common.