Technology is constantly evolving

If technology is constantly evolving, will law enforcement and judicial legislation always be “one step behind” the criminal? Are there any crimes that do not leave behind digital evidence?
Write one page based on the topic and and the book below….
Holt, Thomas J.; Bossler, Adam M.; Seigfried-Spellar, Kathryn C.. Cybercrime and Digital Forensics: An Introduction (p. 518). Taylor and Francis. Kindle Edition.

summary of the chapter, virtually every crime will involve some form of digital evidence, and it is up to law enforcement to be able to identify the possible sources thereof. However, digital evidence may be collected from not-so-obvious devices, such as flash drives disguised as a teddy bear or bracelet