If I work from home but need to come to campus for meetings, can I be reimbursed for mileage expense driving to and from campus, parking, and, if needed, an overnight hotel if I need to be back at campus again the next morning?

Unfortunately no, as those are not reimbursable expenses.

By definition, regardless of where you live, the office location is considered your work location, so travel to that location is considered a commute expense and the IRS would consider reimbursement of that as taxable income. Policy prohibits the reimbursement of expenses that are considered taxable income by the IRS. You can find references to this in UC Travel Policy G28.

One reference is on page 5 pasted below:

"The University’s travel reimbursement procedures contained in this Bulletin are designed to conform to the “accountable plan” rules published by the Internal Revenue Service (IRS). Therefore, University reimbursement of an employee’s travel expenses shall not result in additional taxable income to the employee. Travel expenses considered by the IRS to be taxable income to the traveler are not reimbursable except for the following:"

The expenses we are discussing here are not on the list of exceptions.

Another reference is on page 13, section d:

Expenses for travel between the traveler's residence and headquarters (commuting expense) shall not be allowed.

Another reference is on page 23, section E.1.a:

For hotel expenses it states that "Regardless of the length of time for business travel, the traveler must be at least forty miles from the headquarter location or home, whichever is closer, to be reimbursed for an overnight stay."