Attainder and ex post facto laws 315 Bills of attainder 315 Ex post facto laws 316 Definition 316 What constitutes punishment 317 Changes in place or mode of trial 317 Clause 4. Capitation and direct taxes 317 Direct taxes 317 The Hylton case 317 From the Hylton to the Pollock case 318 Restriction of the Pollock decision 319 Miscellaneous 321 Clause 5. Export duties 321 Taxes on exports 321 Stamp taxes 322 Clause 6. "No preference" clause 322 Clause 7. Appropriations and accounting of public mon 323 Appropriations 323 Payment of claims 324 Clause 8. Titles of nobility and gifts from foreign States 324 Section 10. Powers denied to the States 325 Clause 1. Not to make treaties, coin money, pass ex post facto laws, impair contracts, etc. 325 Treaties, alliances, or confederations 325 Bills of credit 326 Legal tender 326 Bills of attainder 326 Ex post facto laws 327 Scope of provision 327 Denial of future privileges to past offenders 327 Changes in punishment 328 Changes in procedure 328 Obligation of contracts 329 Definition of terms 329 "Law" 329 Status of judicial decisions 329 "Obligation" 332 "Impair" 332 "Contracts," extended to cover public contracts 332 Fletcher _v._ Peck 335 New Jersey _v._ Wilson 336 Corporate charters; Different ways of regarding 336 Dartmouth College case 338