The ICO has just published updated guidance about when personal data can be disclosed without applying the usual data protection principles, if the disclosure is necessary for the prevention or detection of crime.
Some parts of the guidance is aimed at organisations that often process data for crime and taxation purposes, like the police and HMRC and looks at how they can withhold information from individuals when the DPA usually requires it to be provided.
Other parts of the guidance are aimed at organisations that have been asked to provide data to the police, to help them make informed decisions about disclosure.
It should always be remembered that disclosure in these circumstances is discretionary-it allows disclosure, but it does not require it.
The ICO guidance can be found here