Which of the following is not a reason for a warrantless arrest regarding harassment violations?

In the context of warrantless arrests for harassment violations, option C, which refers to evidence collected without a warrant, is not a valid reason for making such an arrest. Warrantless arrests are typically permissible under certain circumstances, such as when a crime is committed in the officer's presence, when there is a risk of evidence being destroyed, or when the suspect poses a threat to public safety.

In cases involving harassment, specific criteria must be met to justify a warrantless arrest. Direct violations of an order (like a restraining order) provide clear grounds for police intervention, as do instances where an individual has notice of an order and subsequently defies it. Defiance of police orders can also provide a lawful basis for a warrantless arrest if it escalates into a situation where immediate intervention is necessary.

However, the mere collection of evidence without a warrant does not suffice to warrant an arrest under harassment laws. The legality of the evidence itself does not dictate whether an arrest can be made; rather, it is focused on the immediate circumstances surrounding the alleged harassment and any previous legal orders in place. Therefore, option C stands out as the correct choice since it does not constitute a recognized legal basis for a warrantless arrest in harassment scenarios.