Who Stole the Tarts?

The King and Queen of Hearts were seated on their throne when they arrived, with a great crowd assembled about them--all sorts of little birds and beasts, as well as the whole pack of cards.  'I wish they'd get the trial done,' Alice thought, 'and hand round the refreshments!' But there seemed to be no chance of this, so she began looking at everything about her, to pass away the time.

The judge, by the way, was the King; and as he wore his crown over the wig, he did not look at all comfortable, and it was certainly not becoming.

'Consider your verdict,' the King said to the jury.

'No, no!' said the Queen. 'Sentence first -- verdict afterwards.'

Use both maps to crack the code,
and remember:  X Marks the Spot

The thief is hiding under the stone stairs
in the main entryway of the indicated building