Energy companies use persistent and personalized pressure to get landowners to give permission for hydraulic fracturing (fracking), and even when landowners decline, companies use legalized compulsion to conduct fracking anyway, according to a new study led by researchers at Binghamton University.

Since a well is only economically viable if you can drain a large spatial area from a single well, drilling companies have to pool multiple mineral claims into a single working contract before drilling. But landowners often hold out from such deals for various reasons—they might be wary of the potential health risks, holding out for more money, or they simply might be unreachable.

This is where compulsory unitization comes in. It’s a law that many oil- and gas-producing states have in which if some percentage of the land on top of an oil/gas reservoir is owned by people who have already given permission for drilling, then the owners of the remaining land can be compelled to join the drilling. For example, if there are 1,000 acres of land on top of a gas deposit, and the owners of 650 acres have given permission, the owners of the remaining 350 acres of land can be compelled to join.