“…The literature studying incomplete enforcement environmental policy includes Harford (1978Harford ( , 1991, Viscusi and Zeckhauser (1979), Harrington (1988), Jones (1989), Kambhu (1989), Shaffer (1990), Xepapadeas (1991), Malik (1990Malik ( , 1993, Keeler (1991), Segerson and Tietenberg (1992), Chua et al (1992), Swierzbsinski (1994), Garvie and Keeler (1994), Huang (1996), Lear and Maxwell (1998), Cohen (2000), 2 Heyes (2000), Polinsky and Shavell (2000), and Hu et al (2004). Harford (1978), Viscusi and Zeckhauser (1979), and Jones (1989) assume a perfect competition market structure and discuss the effects of environmental standards and penalties on environmental quality.…”