Bush has resorted to issuing constitutionally dubious "signing statements," which declare, by fiat, how he will interpret and execute the law in question, even when that interpretation flagrantly violates the will of Congress. Earlier presidents, including Jackson, raised hackles by offering their own view of the Constitution in order to justify vetoing congressional acts. Bush doesn't bother with that: He signs the legislation (eliminating any risk that Congress will overturn a veto), and then governs how he pleases -- using the signing statements as if they were line-item vetoes.
President Obama has irked close allies in Congress by declaring he has the right to ignore legislation on constitutional grounds after having criticized George W. Bush for doing the same.
