There are several recent reports about about the economic cost / benefit analysis of CLCs, including reference to empirical data:

All of these reports are found easily by your usual search engine such as Google.

 

Access to Justice Arrangements, Productivity Commission, Report, September 2014

Early Intervention Measure and Alternative Dispute Resolution, NACLC and Ors, November 2013

Legal Australia-Wide Survey 2012, NSW Law and Justice Foundation, 2012

National Legal Needs & Strategic Planning Project: Queensland, Judith Stubbs and Associates, February 2012

Economic Cost Benefit Analysis of Community Legal Centres, Judith Stubbs and Associates, June 2012

The Economic Value of Legal Aid, PricewaterhouseCoopers, 2009

The Economic Value of Community Legal Centres, Institute for Sustainable Futures, 2006