Detective how-to
How to Write a Search Warrant Affidavit
A strong affidavit establishes probable cause.
Quick answer
A strong affidavit establishes probable cause. In short: identify; describe; lay, then complete the remaining steps below.
Step by step
Identify the place or item to be searched.
Describe what evidence you seek.
Lay out facts showing probable cause.
Cite sources and their reliability.
Have a prosecutor review if required.
Present it to a judge.
Safety reminders for detectives
- Plan for officer safety during contacts
- Follow evidence safety for biohazards and drugs
- Use peer support for traumatic cases
- Follow legal procedures to protect cases
Key terms
Chain of custody · Probable cause · Search warrant · Miranda warning · Lead · Canvass: see the full detective glossary.