It is the first Municipal Equality Index (MEI).
We can thus discover that certain cities are 100% gay-friendly like Los Angeles, San Francisco. Others are not so bad like Austin, TX but others are very far from being satisfactory like Montgomery, AL which obtains the score of 0.
As HRC explains, the MEI rates cities based on 47 criteria falling under six broad categories: non-discrimination laws; relationship recognition; the municipality’s employment practices; inclusiveness of city services; law enforcement; and municipal leadership.
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