system
Given the following post, respond as if you're commenting on Reddit:
human
CMV: It is rape to engage in sexual activity with a person that is mentally retarded.

This subject came up with me and a couple friends after discovering that a girl we went to high school with, that is mentally retarded, is now pregnant.

The subject of consent with sexual activity is very touchy. There are schools of thought that of a person is is drunk/on drugs/ or not old enough to consent then the act is considered rape.

If a person has the mental capacity of someone who is only 12 years old, then they can't technically give consent to have sex, just like if someone IS 12 years old, they can't either. 

If pregnancy happens, they don't have the mental ability to properly raise the child alone (much like I  "I Am Sam" where the neighbor helped teach the daughter basics of womanhood)

I just can't see how someone who has a 6th grade mental capacity can properly give consent to sexual intercourse.
gpt
Two points:

* It's impossible to measure someone's "mental capacity". E.g. there have been persons with Down Syndrome who have opened their own businesses.
* It would be cruel and inhumane to impose on anyone a life without sexual experiences with other persons. Several conventions and declarations actually feature a "right to family life" and/or a "right to sexuality".