Shields have been used since prehistoric times, starting with hunters, who used them to conceal and protect dangerous giant animals, who attacked with hand-held weapons such as clubs, axes and spears. After proving themselves highly effective, they entered the field in hand-to-hand combat and served as cover for arrows and other missiles of the day. They are no longer favored by modern hunters, but they remain on the battlefield to this day. They are also used by law enforcement and prison guards as a non-lethal tool for controlling riots, clearing rooms, and isolating and immobilizing combatants. They are used in formations and one-on-one encounters, as well as for offensive and defensive purposes.
Riot control shields need to be lightweight and comfortable to hold and operate for extended periods of time. Shield angles need to be adjusted quickly and easily to block or deflect threats as much as possible. Additionally, the shield position needed to be easily adjusted so that the officer could move forward or backward, or even run if needed.
Riot control shields are usually not bulletproof because they are made of clear polycarbonate and similar plastics. They can take blows from clubs and clubs, as well as missiles thrown like rocks. They might slow bullets slightly and improve the performance of body armor commonly worn by police and military, but that shouldn't be counted on.
Ballistic shields aka tactical shields are a stronger variant that look somewhat similar to riot control shields but are made of heavier materials that stop or deflect bullets. Of course, it's hard to really call anything "bulletproof" because there are so many variables like distance from the gun, caliber, etc. However, bulletproof shields are definitely bulletproof, and being used by police and military personnel as a riot control shield would not be up to the task.
In the United States, riot control shields are unrestricted and can be purchased by law-abiding citizens. However, felons can and are restricted from possessing them, as they may be subject to body armor restrictions under federal law. In some areas, laws may restrict civilians from using or carrying riot control shields, so be sure to check all local regulations regarding shields before purchasing one.
Like riot control shields, ballistic shields can generally be purchased by law-abiding citizens. Felons may be restricted from owning them, and in some areas, laws may restrict civilians from using or carrying riot control shields, so be sure to check all local regulations regarding shields before purchasing one.