A panel for a display device includes a display unit, an electrostatic protection wire, a wire being connected to the display pixels, an electrostatic protection circuit, and an electrostatic protection circuit control line. The display unit includes a plurality of display pixels. The electrostatic protection wire is connected to a test pad, the test pad being provided to receive a test signal. The electrostatic protection circuit connects the electrostatic protection wire and the wire connected to the display pixels. The electrostatic protection circuit includes a back-gate-type transistor that has a gate electrode, a drain electrode being short-circuited with the gate electrode, and a back-gate electrode. The electrostatic protection circuit control line includes a first end and a second end, the first end being connected to the back-gate electrode of the back-gate-type transistor.