Eliezer is right: RobertLumley's friend is mistaken:

can the value of your time and services while providing pro bono legal services qualify as a charitable contribution that is deductible from gross income on your federal tax return? Unfortunately, in a word, nope.

According to IRS Publication 526, “you cannot deduct the value of your time or services, including blood donations to the Red Cross or to blood banks, and the value of income lost while you work as an unpaid volunteer for a qualified organization.”