Some courts require that a factual basis be established before a guilty plea can be entered.  Some state courts satisfy this requirement by means of a simple stipulation that there exists a factual basis for the plea, without specifying what it is, that is entered into by defense counsel and the prosecution.  Others, such as California, require that the source of the factual basis be identified, such as an offense report, preliminary hearing transcript, and the like.[138]  This requirement is particularly common in federal court.

[138] People v. Holmes, 32 Cal.4th 432 (2004).

RECORD OF CONVICTION - POLICE REPORTS
Shepard v. United States, __ U.S. __ (March 07, 2005) (a court sentencing under the Armed Career Criminal Act may not look to police reports or complaint applications to determine whether an earlier guilty plea necessarily admitted, and supported a conviction for, generic burglary).
http://laws.findlaw.com/us/000/03-9168.html      Relying on its sentencing enhancement cases, the First Circuit has refused to bar an immigration factfinder from examining a police report as part of the record of conviction in determining whether a noncitizen has been convicted of an aggravated felony. Emile v. INS, 244 F.3d 183 (1st Cir. 2001) (relying on United States v. Harris, 964 F.2d 1234 (1st Cir. 1994) and United States v. Shepard, 231 F.3d 56 (1st Cir. 2000) to hold that there is no due process problem where factfinder considers police report as part of the record of conviction).  Yesterday's Shepard decision overruled United States v. Harris, 964 F.2d 1234 (1st Cir. 1994) and reversed Shepard.  In light of this development, practitioners may take the position that Emile is no longer good law regarding whether police reports are part of the record of conviction because the Supreme Court has expressly rejected the reasoning on which it relied.      Thanks to Dan Kesselbrenner for this analysis.