Ed and Lorraine Warren stopped actively investigating paranormal cases primarily due to Ed Warren's death in 2006 from complications following a stroke. Lorraine Warren retired from active investigations shortly after Ed's death but remained a consultant to their organization, the New England Society for Psychic Research (NESPR), until her own death in 2019. Their investigations had spanned over several decades during which they reportedly investigated more than 10,000 cases. The Warrens shifted from active fieldwork to roles focused on their museum and legacy after Ed's passing, with their son-in-law taking over leadership roles related to their work and museum.

Additional context includes controversies and serious allegations about Ed Warren's personal life and the authenticity of some investigations, which also affected their reputation in later years. However, these issues were not explicitly cited as direct reasons for stopping investigations but part of the overall narrative surrounding their careers.