Yes... parents and guardians sterilize their children or wards who are mentally handicapped all the time.. it is nothing new and often the state acts as an intermediary helping the parents/guardians get the legal work done. There are a few news stories about this on the web, but usually it gets no media attention at all.
http://repository.upenn.edu/cgi/viewcontent.cgi?article=1005&context=josnr
The scary part is that there are over 14 US states that still have the forced sterilization laws on the books, laws put in place long ago by eugenics fanatics. Granted at the moment those laws are not being enforced, but still scary that they are there and can be used at any minute.
But as long as it is a case by case valuation and not a blanket order like under the American eugenics laws, then I dont see the problem at all. There is a reason that someone else is the guardian of an over 18 year old.. they are unable to care or choose for themselves.
Yeah .... That paper seems to be outlining the exact opposite of what you claimed
<<<Finally, prior to 2000, only one study mentioned
sterilization issues of two male mentally handicapped
individuals (Elkins et al., 1988). However, in 2000,
Carlson, Taylor, & Wilson designed a survey study
to specifically look at awareness in legal and medical
organizations of male sterilization using surgery or
hormonal control. This study was the first study
to attempt to evaluate any aspect of sterilization of
male mentally handicapped individuals and thus
raises awareness to the lack of knowledge in this area.
However, this study was very poorly designed with very
unclear and inconclusive results. In addition, a low
response rate, no reliability or validity of the survey
reported, and a small sample size (n=51) make any
results difficult to generalize to a broader population.>>>
<<<Finally, in a descriptive study by Elkins et al., a
Michigan clinic received 20 parental requests for
sterilization (1988). After each parent consulted
with an ethics committee to discuss alternatives to
sterilization, state laws and other support issues, only
5 cases were recommended for sterilization. Thus, this
study demonstrates how increased parental support
can decrease requests for sterilization.>>>