There were 203 recorded crimes; the majority (28) occurred in the Metropolitan constabulary.
To many people, a majority must consist of more than half the total – which in this case, would be at least 102 crimes. I believe that in American English this is called a 'simple majority'. I've also heard it referred to as an 'absolute majority' (though I'm not sure whether there's a difference between 'simple' and 'absolute' majorities).
However in British English at least, as this writer demonstrates, 'majority' often means only "the greater number or part" (OED Online). More crimes occurred in the Metropolitan constabulary than in any other; therefore this is where the 'majority' of crimes occurred. I must admit, this usage strikes me as a little odd, and I'm English.
As regards elections, it's worth contrasting 'majority' with 'plurality'. The OED Online describes this as "orig. and chiefly US, the fact of having the largest share of the votes cast, when this is less than an absolute majority".