Police in London are too afraid to pursue suspected criminals on mopeds without helmets, according to a union.
Ken Marsh, Chair of the Met Police Federation, said officers are not protected against repercussions if they put anyone in danger - informed bbc.
But the Met Police said officers "can and will" carry out pursuits if they assess that it is safe to do so.
A former policeman said current rules are leading to the return of "highwaymen" in the capital, .
Mark Wilsmore, who now owns a bikers cafe in north London, said: "We're going back to the 18th Century.
"We've got roving bands of thieving nasty people who have no concern about any enforcement."