Phrenologists argued that certain skull features, such as the shape of the forehead or the prominence of certain areas, could indicate criminal tendencies or moral deficiencies.

This belief led to the establishment of phrenological departments within police forces and the collection of extensive skull measurements from criminals, creating the infamous “criminal skulls” archives.

One prominent example of phrenology’s influence on criminal investigations is the work of Cesare Lombroso, an Italian criminologist of the late 19th and early 20th centuries.

Lombroso, influenced by phrenological ideas, proposed that certain physical characteristics, such as a low forehead, strong jaw, or asymmetrical face, were indicative of a “born criminal.”

He believed that criminals could be identified by their physical appearance and sought to apply this theory to criminal profiling.

Despite the widespread use of phrenology in crime investigations, it faced significant criticism from the scientific community.

Many scholars and scientists rejected the notion that the external shape of the skull could accurately reflect an individual’s mental or moral attributes.

Critics argued that phrenology lacked empirical evidence, relied on subjective interpretations, and was susceptible to bias.

As the 19th century progressed, advancements in neurology and the development of more rigorous scientific methodologies discredited phrenology.

The field lost its appeal among mainstream scientists, and its influence waned in the early 20th century.