It should also get worse as more people are added: In a large enough population almost every person has some look alike who happens to be a thief. Another way

It should also get worse as more people are added: In a large enough population almost every person has some look alike who happens to be a thief. Another way to look at it is for the worst case person what is their false positive rate? It's going to be 100%: Joe Blow, who did nothing wrong to no one, will go from place to place getting kicked out for the rest of his (/the system's) life. The failures aren't random (or at least not entirely)-- some people will get a heap of error in their lap. So while getting punted 1:10000 times you go somewhere unfairly isn't too bad, getting always punted is awful. The unequal distribution of errors creates bad incentives: the system is almost risk-less for those of us who aren't the victims of false hits, so why should we demand improving or banning it?