There was no different colored ink. That is a photoshop job by Fake News GatewayPundit. If anyone saw the press conference on TV (I did), when the woman held up the yearbook it was plainly all in the same color ink. This can also be seen in umpteen pictures of a screen grab of the press conference found on the web.
The problem with the signature in the yearbook is that parts of it don't match up with a recent sample of Roy Moore's signature taken from his candidacy filing papers last summer. Take a look at the "y" in "Roy". Notice it is radically different in the alleged 1977 signature compared to the 2017 signature.
In the 1977 signature the loop on the "y" loops below the letter and crosses the tail of the "y", looping in a clockwise direction. In the 2017 signature the loop on the "y" is far above the other letters in his name and it curls back an opposite, counter-clockwise direction compared to the loop in the 1977 signature.
Also notice the use of hyphens in the date in 1977 and the use of slashes in the date in 2017.
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