If an officer uses information from an undercover informant who is engaged in criminal activity to establish probable cause, the fourth amendment requires in all cases that the officer:

this requires in all cases that the officer provide some information to support the informant or the informant's information

Explanation:

According to my research on the requirements of probable cause and warrants, I can say that based on the information provided within the question  this requires in all cases that the officer provide some information to support the informant or the informant's information. If the officer cannot provide this information then the case is thrown out by the judge because the arrest no longer falls under probable cause.

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- jack watson