02031302-27 Anti police protests as police officers from across the country converged on London for a mass rally to protest at proposed pay reforms..THE line of off-duty police officers waiting to lobby their individual MPs stretched the entire length of the Houses of Parliament for more than half a mile across Lambeth Bridge over the River Thames. .The atmosphere was good humoured, and uniformed officers on duty to "police" the mass rally sounded sirens in support as they drove past. .Leader of the Opposition Iain Duncan-Smith and Liberal leader Charles Kennedy both spent some time talking to the queuing officers. .Two open-top, double-decker buses hired by the national police federation did the rounds of Parliament Square with banners proclaiming "Fair Play For Policing". .Officers started arriving at 11am - by 6pm a total of 10,255 from all over the UK had registered at the conference centre in Westminster. .13 Mar 2002.