I found my Maryland taxes were not correctly calculated when choosing
to itemize deductions. Upon inspection of the output MD 502 form,
I found line 17b (state and local income taxes) was left 0. Turbotax should
have brought over the SALT (State and Local taxes) entry from the federal return to populate this
field. As result, SALT is not removed from the federal itemized deductions
when calculating the itemized deductions for the MD taxable income. For Maryland,
SALT is typically clipped at $10,000 on the Federal itemized deductions. The
result is an over $800 tax error on the MD state return.
Turbotax initially recommended I use the Federal standard deduction on the
"Deductions and Credits" final "You've Chosen Itemized Deductions" dialog,
but (because of the ~$800 tax error) I found I had lower overall (Fed + State) taxes
if I itemized. It's possible that this error only occurs when selecting Federal itemized
deductions when the standard deduction is recommended.