See as appropriate:
In employment law direct discrimination is what its name suggests, ie discrimination in an employment context against a person for a particular reason provided for by statute. In general there is no "justification" defence available in direct discrimination cases (age discrimination is an exception - see Age discrimination/2006 regulations/justification defence ). Instead the law generally provides that it is not unlawful for an employer to directly discriminate against an employee or job applicant if he can show that there was a genuine occupational requirement that a person be of a particular sex/race/religion etc. Thus, for example, it would not be unlawful to require a man and a woman respectively to play the parts of Romeo and Juliet in the Shakespeare play.
As a general rule indirect discrimination occurs where an apparently neutral provision, criterion or practice would put persons of one sex/race/religion etc at a particular disadvantage compared with persons of a different sex/race/religion etc. For practical purposes, although not strictly accurate in law, it can generally be said that indirect discrimination is not unlawful if the provision, criterion or practice can be objectively justified as a proportionate means of achieving a legitimate aim. A simple example of indirect sex discrimination would be a requirement that a job applicant must be over 6 feet tall. That requirement would generally put women at a disadvantage compared to men and so would be unlawful unless justified as a proportionate means of achieving a legitimate aim.
Other miscellaneous points of general interest include:
It seems that Michigan, Santa Cruz, San Francisco and Washington, DC all have laws barring employment discrimination because of weight. In other states, as in the UK, there is no specific provision outlawing weight-discrimination - but this might be the shape of things to come on this side of the Atlantic so this article in the Wall Street Journal may therefore be of interest - see USA: Why Weight-Discrimination Cases Pose Thorny Legal Tests - Wall Street Journal 2nd October 2007.
"In the [Sex Discrimination Act and Race Relations Act], men and women or black and white, as the case may be, are opposite sides of the same coin. Each is to be treated in the same way. Treating men more favourably than women discriminates against women. Treating women more favourably than men discriminates against men. Pregnancy apart, the differences between the genders are generally regarded as irrelevant. The 1995 [Disability Discrimination] Act, however, does not regard the differences between disabled people and others as irrelevant. It does not expect each to be treated in the same way. It expects reasonable adjustments to be made to cater for the special needs of disabled people. It necessarily entails an element of more favourable treatment."