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The BATSE experiment has now observed more than 1100 gamma-ray bursts. Theobserved angular distribution is isotropic, while the brightness distributionof bursts shows a reduced number of faint events. These observations favor acosmological burst origin. Alternatively, very extended Galactic Halo (EGH)models have been considered. In the latter scenario, the currently favoredsource of gamma-ray bursts involves high velocity pulsars ejected from theGalactic disk. To be compatible with the observed isotropy, most models invokea sampling distance of 300 kpc, a turn-on delay of 30 Myrs, and a source lifetime of about 1 Gyr. We consider the global energy requirements of such modelsand show that the largest known resource. rotational kinetic energy, isinsufficient by orders of magnitude to provide the observed burst rate. Moreexotic energy sources or differently tuned pulsar models may be able to getaround the global energy constraint but at the cost of becoming contrived.Thus, while extended halo models are not ruled out, our arguments place asevere obstacle for such models and we encourage proponents of EGH models toclearly address the issue of global energetics.Comment: 18 pages, with 2 figures included. Postscript. ApJ, in pres

Are Gamma-Ray Bursts Due to Rotation-powered High-Velocity Pulsars in the Halo?