The wheeled devices are somewhere in between a Segway with no handles and a skateboard with in-line wheels. They tend to be extremely maneuverable and move slightly faster than a walking pace. Many incorrectly refer to them as 'hoverboards', even though they clearly make contact with the ground. The Metropolitan Police Special Constabulary sent out a tweet yesterday clarifying that the self-balancing scooter is verboten on public sidewalks and streets.
The say a law from 1835 makes it illegal for a person to ride upon any footpath or causeway set aside for foot traffic. The law also refers to the driving of farm animals on such paths, but police are still insisting the ordinance is legit in this case. The scooters need to be registered as motor vehicles before they can be legally driven on public streets, but you can't register one, since it doesn't meet the minimum requirements to qualify as a motorized vehicle. Sounds like a classic Catch 22, though British people are still able to ride these scooters on private land with the landowner's permission. If you take to the streets you've "committed a nuisance" under section 72 of the Highway Act of 1835. Here's what the statue says, according to the Washington Post:
If any person shall wilfully ride upon any footpath or causeway by the side of any road made or set apart for the use or accommodation of foot passengers; or shall wilfully lead or drive any horse, ass, sheep, mule, swine, or cattle or carriage of any description, or any truck or sledge, upon any such footpath or causeway; or shall tether any horse, ass, mule, swine, or cattle, on any highway, so as to suffer or permit the tethered animal to be thereon... every person so offending in any of the cases aforesaid shall for each and every such offence forfeit and pay any sum not exceeding level 2 on the standard scale, over and above the damages occasioned thereby.
So there you have it, alternative transportation fans. No cluttering up the sidewalks with your livestock, and keep your weird scooters at home.