Under what condition can DNA be collected from a person arrested without a warrant?

The correct answer is that DNA can be collected from a person arrested without a warrant under certain conditions established by legal precedent, specifically in relation to a probable cause hearing.

In general, law enforcement agencies are allowed to collect DNA samples from individuals who have been arrested for certain serious offenses after a lawful arrest. This is grounded in the understanding that individuals booked for serious crimes have a diminished expectation of privacy regarding their identity. Collecting DNA at the time of arrest or shortly thereafter typically aligns with the procedures in place once probable cause is established.

When a probable cause hearing is conducted, it allows a judicial officer to review the evidence to determine whether the arrest was justified. Until that determination is made, the collection of DNA may be seen as premature, as it relies heavily on the validity of the arrest itself. Thus, without a proper legal basis reflected in a probable cause finding, DNA collection would not be advisable or permissible.

The other scenarios presented do not align with the legal standards for DNA collection. Simply being arrested does not automatically permit DNA sampling; other conditions must be satisfied. Confession to a crime or being a repeat offender does not by themselves create a basis for immediate DNA collection without considering due process protections.