Royal Parks Constabulary Sir John Biggs-Davison asked the Secretary of State for the Environment (1) how many houses are available to the royal parks constabulary;(2) what increase there has been in the last decade in the use of motor vehicles by police and other services in the royal parks; and if he will require it to be kept to a minimum for the avoidance of pollution. Mr. Macfarlane I will answer these questions shortly.