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Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

The Board of Directors
PacWest Bancorp:

        We consent to the incorporation by reference in the registration statements on Form S-3 (No. 333-144320) and on Form S-8 (Nos. 333-43330, 333-101025, 333-107636 and 333-138542) of PacWest Bancorp of our report dated February 27, 2009, with respect to the consolidated balance sheets of PacWest Bancorp and subsidiaries as of December 31, 2008 and 2007, and the related consolidated statements of earnings (loss), stockholders' equity and comprehensive income (loss), and cash flows for each of the years in the three-year period ended December 31, 2008 and the effectiveness of internal control over financial reporting as of December 31, 2008, which report appears in the December 31, 2008, Annual Report on Form 10-K of PacWest Bancorp.

/s/ KPMG LLP  

Los Angeles, California
February 27, 2009

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Exhibit 23.1
Consent of Independent Registered Public Accounting Firm