62 Pa. Stat. § 2257
For the purposes of the institution district and for the payment of the obligations of the predecessor poor district, the commissioners of each county shall have the power to levy and collect on real estate, trades, occupations and professions, and in fourth to eighth class counties per capita on individuals, in the same manner and at the same time as county taxes, annual taxes to pay the current expense of the institution district, none of which shall exceed ten mills on the dollar of the last adjusted assessed valuation for county purposes: Provided, That no tax shall be levied and collected on trades, occupations and professions at the same time a per capita tax on individuals is levied and collected. The commissioners may, by resolution, abolish taxes on trades, occupations and professions for the purposes of the institution district and for the payment of the obligations of the predecessor poor district. The commissioners may also levy such annual special taxes as may be needed to pay interest and sinking fund charges on bonds issued to pay for the purchase of lands or buildings, or for the erection and equipment of buildings, or for the payment of debts of the institution district. Such taxes shall be levied at the same time as the county tax, and shall be collected in the same manner, and subject to the same discounts and penalties, as the county tax.
Any per capita taxes levied upon and collected from any person shall not in any one year exceed a total of three dollars ($3) for county and institution district purposes.
62 P.S. § 2257