Family: a social unit consisting of one or more adults together with the children they care for.
Yes, homosexuals should be able to adopt. First, all the adopted children are wanted. As with traditional couples, homosexuals have to go through the same extensive screenings and pay substantial fees to be able to adopt. The word family does not define the adults in the unit by sex, gender identification or gender preference; just adults who have children under their care. What better environment could a child be in when parents want to love and nurture another small human? It would be a poor assumption that the nature of the love and nurturing would be any different than a traditional man woman couple. Some may argue that a gay couple will turn a child gay; that’s ludicrous. Being gay in something born within and can’t be switch on or off under environmental influence. Place children in homes where they are wanted.
People like to point out that homosexuals should not raise children, because the child risks missing out on essential parenting qualities. This argument makes no sense mainly because:
1) There have been happy and healthy children who were raised by homosexual parents, rendering the generalisation of this argument faulty.
So 2) If the wellbeing of the child is truly the concern that make people support governmental intervention, a better strategy would be to force parents to pass for a "parenting test" before they're allowed to raise children. That way you filter out bad parenting in a more efficient, and less discriminating way.
(whether or not I would support such a test is beyond the point, I merely raise it to make a point against the principle)
A mother and a father provide the best environment for a child to grow up in. As long as there remains a huge waiting list we can choose to put children with the married couples first. That may not be what gay couples and single people want, but the interest of the child is primary. If there is a child that was to be put up for adoption and you had to make a choice between a straight couple, a gay couple, a lesbian couple. All couples are of the same age, education level, same environment, same number and gender of adopted children etc. All things are the same except the gender and sexual preference of the parents. Which couple would you pick? Or would you throw a dice?