Police drivers generally will be picking up a car that is used by others (and who knows what they were doing in the last shift?).
As
MGF says any starting drill needs to be customised to meet your specific circumstances. A car which has only one driver will need a lot less prep (I only check my seat position if I'm picking it up from the garage!).
Generally I always do a quick look round for damage and check the tyres still appear inflated. Oil, water, pressures,lights etc are checked weekly (or before a long journey), tread depths (and spare generally) monthly.
Shared works vehicles should be checked every time, at least in terms of basic roadworthiness - you don't know what the previous user has been up to in it (works vans get serious abuse), and you have little control over your employers maintenance standards (can you be sure any claimed checks have actually been done to a minimum adequate standard, and any results acted upon?). Less concerned about oil and water - if they choose to ruin their engines through poor maintenance, it's their money - but I'd want to know that it's not going to kill or land me with points on my license. Get caught driving an unroadworthy vehicle and it's on you legally speaking.
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