Law enforcement "service weapons" vary widely, and the standards are usually set by the individual departments and agencies. Most agencies try to standardize on one weapon and one caliber to ease purchase, maintenance, and training problems. Most, but not by any means all, have gone to semi-automatic sidearms which fire 9 millimeter, 10 millimeter, .357 caliber ,40 caliber, 45 ACP caliber, and 45 GAP ammunition. The most common manufacturers are probably Glock, Beretta, and Sig Sauer, but other manufacturers are also represented. Smith & Wesson is trying to get their M&P pistol into the Law Enforcement market by offering low cost swap out or even free swaps.
There are some departments which traditionally carry unique sidearms (e.g. - The Texas Rangers carry the old-military-style .45 caliber Colt sem-autos). Some departments still carry (or allow their officers to carry), revolvers, which typically fire 38 caliber, 357 caliber or 45 caliber ammunition. Probably the most prevalent heavy weapon assigned to duty officers in the field (exclusive of special assignment units such as S.W.A.T. teams) is overwhelmingly the Remington 870 12 gauge shotgun, but here to, many other makes abound.
Not exclusively. Police carry many different types, styles and finishes of firearm.
If you mean in real life, it just depends on what the local police department requires. If you mean the TV show, I have no idea.
Guns, tasers, police sticks, walkie talkies, etc.
it used machine guns
to arm there selves if they need to use it and to have the advantage
Ranges, certain situations.
A long metal stick
MjolkDrikker 22mm
Sig Sauer P229
Hawaiian police use standard radar guns. They also use laser guns to catch speeder and have been doing so since the 1980's.
The only police to use firearms in the UK, are specialised groups such as the Civil Nuclear Constabulary, or special teams within territorial police forces. When the metropolitan police force was established, officers did not carry guns.
They had involuntarily handed over their guns to the police.