Is it a violation of religious freedom to ban beards for prison inmates?

The Supreme Court just granted cert in Holt v. Hobbs...

... is a case filed directly by an inmate, in a hand-written petition.

The claim of entitlement to wear a beard for religious reasons, in spite of the general rule against beards in prison, is premised not on the constitutional right to free exercise (which authorizes government to impose neutral, generally applicable rules even though they burden religion), but on a statutory right to hold government to a strict scrutiny standard when it puts a substantial burden on religion. The statute in question is not the work of some backward state — as a layperson familiar with the recent to-do in Arizona might imagine — but the Religious Land Use and Institutionalized Persons Act, adopted by unanimous consent in the U.S. Senate and the U.S. House of Representatives and signed by President Bill Clinton in 2000.

ADDED: 2 weeks ago, we were talking about another case involving prison, hair, and RLUIPA, in which Supreme Court review is being sought. That case, from the 11th Circuit, is called Knight v. Thompson. We also talked about it last summer, and I showed you an old exam from my Religion and the Constitution class that depicted 5 different prisoners with different reasons — some religious — objecting to a rule requiring short hair.

It was very interesting to me to see how students would respond to the 5 different needs for long hair. If I remember correctly, most students found the Sikh's interest so strong that they began there. But then what happens? Do you include all? Just the Rastafarian-inspired man?  None of the others? And does thinking about that make you want to exclude the Sikh too? If your answer is yes, then you may be an 11th Circuit judge.