Who says that referee must wear black shrit? EPL referee wears green and red! Most of them wear black but depends on the colour of jersey wear by the both team. If the contrast of the colour is dark, they will either wear red or green! Like the match against MU and Chelsea, the referee mostly will wear black because it is easy to see; But like Chelsea vs. Arsenal, the referee will wear green!
FIFA's referee also wears yellow, and how dare you says referee 'ONLY' wears black????
Referee's jersey colour: Red, Green, Yellow, Black
因为队员不穿黑衣服,有别于队员
由于历史上某界世界杯上球场上球员犯规太多,而裁判却没有明显的作用,看台上的一个警察吹响了警笛,场上的球员听到警笛停止了犯规动作,此后,球场上的裁判就采用了黑色的衣服,一方面是区别球员,一方面是裁判的威严不可侵犯