On Thursday, the District will begin to ticket and tow vehicles that violate the rules governing parking for disabled people at the new meters with the red tops.

Park at those street spaces only if your vehicle displays a valid placard or license plate for people with disabilities and pay the meter rates, the District Department of Transportation said in a reminder notice today.

The District has been installing the meters, but issuing only warning notices to violators during February.

About 400 such meters have been installed in the D.C. central business district and areas around federal buildings in Southwest Washington. DDOT says the goal is to improve access for disabled people to businesses and services in the central part of the city.

Drivers who do have a valid placard or plate can park for twice the normal time at these meters, but they do have to pay during the designated hours of operation.

DDOT gives this example: If the meter rate on the block is $2 an hour with a two-hour time limit, a vehicle for a disabled person can legally park at a red top meter for four hours, with a payment of $8. (Drivers can pay by cellphone as well as through the meter.)

The old system of free parking for the disabled was marred by cheating, DDOT said. The new system, an “all must pay” program similar to the one used in Arlington County, removes that incentive.

One question I often get is whether authorized plates and placards from outside D.C. are good for parking at D.C. spaces for the disabled. The answer is yes, the District does recognize them as valid in the city. You can’t make up your own sign and expect to avoid a ticket, however.