Green’s Dictionary of Slang

upright man n.

also upright cove
[his stance. He adopted no form of counterfeit physical deformity, as did many of his peers, in his pose as a solid citizen. As such he both gulled the public and commanded loyalty and financial dues from lesser thieves]

[mid-16C–early 19C] (UK Und.) a senior criminal beggar, outranked, if at all, only by the ruffler n.. Such a villain held absolute power, demanding and receiving both cash and kind, including their women, from his inferiors and beating them without fear of revenge.