The opposite of respect for equality is a tolerance of inequality. This means that other groups of people are given privileges, while others are exploited. No leader should tolerate the exploitation and oppression of other people. If we tolerate this sort of hierarchy, then we are no better than the tyrants of history.
The only qualification should be age and nationality. Not only can you not measure respect for equality, but even if you could, the person is free to respect or disrespect equality all they want. The qualifications for officer (aside from age and nationality) should not be set in law, but by how we vote. If we want people with respect for others, we need to vote for them, and if we don't care about that, than don't worry. We need to choose who can be elected by how we vote, not with laws.
It's crucial for those in political office to have respect for equality, and if they show disrespect for others of different cultures and races than they should definitely not hold a position in office. However, one cannot quantify respect, and therefore it can not be a prerequisite for a political position.
Although we have progressed significantly in the last 50-60 years, equality is not a universally accepted, thus it does not need to be a basic qualification. If a politician choose not to endorse equality, his approval will be shown in the way the voters think. We are a democracy and if the majority of people are not approving of a politician's standings, they have the right to not vote for him/her.