Are you asking for an accounting course? The answer is not a yes or no like you hope to find.
Here's a professional discussion on the subject
http://www.proformative.com/accounting/accounting-concepts/discussions/audit-tax-fee-accrual
One of the better repulse cites
Margaret - I think because we sign contracts with the CPA firms we accrue in the period incurred via contract versus when the work is performed. Here is the cite - It's Concepts 6:
.05 Accrual of Audit Fee
Inquiry—A CPA has been engaged to audit the financial statements of a client company. The audit is being conducted after year end. Is it proper to accrue the audit fee as an expense of the year under audit?
Reply—According to FASB Concepts Statement No. 6, Elements of Financial Statements, paragraph 145 , "The goal of accrual accounting is to account in the periods in which they occur for the effects on an entity of transactions and other events and circumstances, to the extent that those financial effects are recognizable and measurable." The audit fee expense was incurred in the period subsequent to year end. Therefore, it is properly recorded as an expense in the subsequent period. However, fees incurred in connection with planning the audit, together with preliminary procedures (e.g., confirmation work) would be accruable for the year under audit.
But this is not GAAP and the next comment notes
I am impressed that you were able to find this citation, not many folks know about it. It is in fact an AICPA Technical Q&A which is not an authoritative source of US GAAP. However some firms have adopted it as if it were in fact US GAAP when it is not. US GAAP in this area is not fully defined. I beleive it is acceptable to adopt a policy consistent with the Q&A or accrue in full under a FAS 5 theory.
Ultimately both arguments are valid and best practice would depend on the company. Is the company audited yearly with predictable expenses that are accrued over the year? Is this an unforeseen audit where no accruals have been made.
GAAP leaves some gray area for this subject. As I said it's not an either or.