Victorian police will be given new powers to secretly search homes - for crimes that could include theft and minor assaults - if the Napthine government is re-elected.

Lawyers have criticised an exposure draft for a new state government bill to overhaul criminal investigation powers, saying they will lead to more children as young as 10 being fingerprinted.

Under the proposal, quietly released by the state government this week, the threshold for obtaining fingerprints and DNA samples would be reduced.

Fingerprints and DNA samples would be able to be obtained from people "suspected" on reasonable grounds to have committed a relevant offence, rather than the current threshold of "believed" to have committed an offence.