The practice of a government official holding two or even three jobs, all on the people's payroll is known as 'double dipping'.  There can be serious ethics issues as the different jobs may have conflicting interests.  It also allows lawmakers to pad their retirement in a way no one in the private sector could ever do.  At the same time, they likely aren't committing the full time each job demands. 

 And guess what?  Surprise, surprise--no where is it more prevalent than it is in New Jersey.  Thirty-eight states have laws against the practice.  In Illinois, it is a felony for a politician to double dip.  In New Jersey, it is business as usual.