Signatures over time tend to get simultaneously more stylized and more lazy with less lifting of the pen. That’s an “S” or it was at one time, morphing into just an upswept loop attached to the “y” in “Roy.”
That makes sense. It makes his written Chief Justice signature consistent with the name printed below. It also explains why the yearbook autograph lacks the flourish — he simply signed the yearbook without including his middle initial.
'Tis really sloppy, however. Here is how a cursive capital S is supposed to be written: