The order is to remove about 33,000 inmates from the prison system. Transferring them to local jails requires more funding for those facilities, thus the tax proposal. And of course, this itself is only a short term bridge, not a solution.
Consider the following from The Sacramento Bee, Jan 26, 2010 (http://blogs.sacbee.com/capitolalertlatest/2010/01/corrections-sta.html):
"As of Dec. 31, 2009, California prisons had 22,173 inmates with an immigration hold or potential immigration hold, according to a Department of Corrections and Rehabilitation analysis. That represented 13 percent of the state's 168,830 inmates."
These "immigration hold" individuals remain a potential burden to the taxpayer system whether they are inmates or walking free. However, by simply implementing the law of the land, these individuals can be removed from the prison system and from the country, while they work on correcting the particular "hold" that exists on their immigration status.
It is interesting that the courts (and California) ignore the immigration status of the inmate population, and instead concentrate on the "grossly inadequate provision of medical and mental health care," that the court identified in its 5-4 ruling (http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2011/05/23/BAGK1JJQRJ.DTL#ixzz1NIUNqQTZ) as a right to which every inmate is apparently entitled.