Lucknow, 24/6: An alleged affair with a lady constable cost an Uttar Pradesh deputy superintendent of police (DSP) dearly as he was demoted back to the post of constable from where he had been promoted as the DSP after passing departmental examinations..Kripa Shankar Kanaujia, who had joined Uttar Pradesh police as a constable, had worked his way through hard work and successfully clearing the departmental examinations and was promoted head constable and then to inspector and finally a DSP a few years before.