improper custody 300 words

Describe what is meant by "chain of custody" and why it is important to an investigation.

Provide an example to show how improper custody can damage a case (hint: put yourself in the position of the defense attorney).

Improper custody can certainly impair or even destroy an investigation. Is this in the best interests of justice? Should valid physical evidence be excluded due to improper custody? Explain and justify your position.