When someone touches a surface without gloves, do they always leave fingerprints behind?

The correct choice states that fingerprints may not always be left behind; instead, there must be sufficient contact to create a readable impression. Several factors influence whether fingerprints will be transferred onto a surface, such as the pressure applied during contact, the condition of the surface, and the state of the skin on the fingertips.

When someone touches a surface, if the contact is light or fleeting, it may not create enough of an impression to leave behind a fingerprint. Additionally, the surface type matters; smooth and non-porous surfaces are more likely to retain fingerprints than rough or porous surfaces.

Furthermore, the composition of the skin oils and sweat on the fingers can also affect the transfer of fingerprints. If the skin is dry or the individual has very little natural oil, this may reduce the likelihood of leaving behind an identifiable print. Therefore, sufficient contact is crucial for a fingerprint to be deposited and subsequently identified as evidence in forensic investigations.