Usually a warrant follows the investigation when a DA feels enough evidence is collected to get a conviction (to avoid double jeopardy) and is the official way of doing it. In some countries provision is made for an occasion on which somebody may catch another in the process of committing a crime; commonly called "citizen's arrest", the law normally states that a person, whether uniformed officer or member of the public, can place another person under arrest if they have reasonable suspicion that the other has been/is in commission of a crime.
Yes the officer will have to show both the warrant as well as his I.D . before he arrests you. ANOTHER VIEW: IN THE UNITED STATES: The first answer is not correct. The only thing the officer is required to have is knowledge that a valid warrant DOES exist. He is NOT required to show it to you.
Yes and no. If the Police have witnessed you committing, attempting to commit, or know you have committed a crime they can arrest you with our a warrant. If they suspect you of committing a crime and have very limited evidence they cannot arrest you with out presenting this evidence to a judge to get a warrant.
No. Most often just knowledge that a person is wanted is sufficient to make the arrest.
No. Searches incident to arrest are an exception to the warrant requirement.
Yes, of course. An arrest warrant is a command from a judge to arrest a person. Usually a police officer has no choice and must arrest.
No.
No, a police officer cannot issue a warrant for your arrest only a judge or court magistrate can do that.
It does not seem reasonable or possible.
A police officer must have probable cause in order to arrest someone. They can arrest a person if they see a crime taking place or if an arrest warrant has been issued.
no
Without a warrant you must find reasonable grounds to arrest someone, whereas with a warrant your reason to arrest the suspect already exists. Without a warrant a Police Officer can arrest anyone without permission of a Magistrate as long as they follow the correct procedures so their arrest is lawful, which is unlike an arrest with a warrant where you must be granted the warrant to be able to arrest that person. Without a warrant, a Police Officer can mess the arrest up and make it an unlawful arrest but with a warrant it is very unlikely that they make it an unlawful arrest.
Probable cause or warrant
A person is "under arrest" when a police officer charges them with a crime and chooses to take them to the police station to be processed for it. For example, if someone commits a crime, they are technically under arrest when a police officer witnesses the crime or has a warrant for the arrest and tells the criminal "You are under arrest." Typical procedure after this is to put handcuffs on the criminal and read them their Miranda rights (you have the right to remain silent etc). Handcuffs alone do not mean arrest, but i'm pretty sure its illegal for a police officer to handcuff someone without grounds to arrest them. As a side note, the person doing the arrest does not have to be a sworn in police officer. In Citizen's arrest cases, anyone with arresting powers like a bounty hunter can also place someone under arrest.
A "stop and frisk search," where police search you for their protection or incidental to an arrest; or when contraband is in plain view of the officer.
If the officers can accurately identify the person wanted, or can verify a proper warrant then they will likely arrest you.
If there is a warrant out for you and the police know where you are, they can arrest you.