License Plate Covers, Brackets, Legibility, Fastening, Positioning

The visibility of license plates in Maryland is well detailed in motor vehicle law. Even people who put a totally clear license plate cover over top of their registration plate are subject to fines. And customized diagonal plates are a no-no. Here's what the law says:

TA 13-411 Display of Registration Plates and Tabs

Plates required at front and rear
Not all vehicles are required to have front and rear plates attached to their bumpers, such as class F tractor trailers, but most vehicles are (including passenger vehicles). Police may only stop Maryland registered vehicles for failing to attach their registration plates at the front and rear of their vehicles. Police may not effect stops on out of state vehicles. The law specifically states the plate must be "attached" meaning that the plate is fastened in some manner to the vehicle. Experts debate the use of plastic ties, glue, tape, screws, bolts, string and other materials as means of fastening the plate. The plate must be positioned securely.

How plates should be fastened
Plates must be "securely fastened" and in a "horizontal manner" and "in a manner that prevents the plate from swinging." So if that zip tie happens to break off or the duct tape loses its stick one could argue that the plate was not secure. And if you only have one screw in the top corner then it would be reasonable to assume that plate may swing and that vehicle is in violation. Or, as in the case of many motorcycles, if the plate is attached vertically so the letters can only be read by turning one's head sideways, the plate is in violation of the horizontal rule.

*As of 2020, a “border” or “frame” on a registration plate can only be enforced as a secondary action by Police* 

Plate legibility
Plates must be "maintained free from foreign materials" including registration plate covers. Plates must be "clearly legible" and in a position that is "clearly visible." So, police may have probable cause to stop a vehicle if the plate is covered by dirt, markings, tarps, and even snow. If you happen to have backed into a pole recently and the plate is mutilated, bent, torn or damaged, that may be a violation of the "clearly legible" rule. Furthermore, if you plate is inserted inside the indented portion of a bumper or tucked back into the front grill, the plate may be violating the "clearly visible" position rule. This usually applies to aftermarket bumpers and tail gates.

Registration plate covers
Maryland lawmakers explain what a plate cover is in TA 13-411.1. It includes any registration plate that is

• tinted
• colored
• painted
• marked
• clear
• illuminated

which is designed to

1. cover any characters of the plate (such as month and year stickers, numbers, letters, hypens, the word "Maryland" etc.); or
2. distorts the characters. 

A person may not sell registration plate covers, either. 

Fines/Penalty

TA 13-411(a) Failure to attach plates at front and rear (MD only) $70.00/0 points

TA 13-411(c) Failure to property maintain and fasten veh. reg. plate in visible position (MD only) $70.00/0points