Jerry Jones reportedly won’t join Daniel Snyder if there’s a legal challenge to the NFL’s salary-cap penalties. (John McDonnell / Washington Post)

If Washington Redskins owner Daniel M. Snyder chooses to file a lawsuit to challenge salary-cap penalties imposed on the Redskins and Dallas Cowboys, don’t expect the Cowboys to participate.

“We are not involved,” a Cowboys source told ESPN’s Ed Werder, “and we won’t become involved.”

The Washington Post reported that the Redskins were considering whether to seek an injunction that would delay the start of free agency as they attempt to recoup cap space lost when they were penalized by the NFL last year. The Redskins lost $36 million in cap space (divvied up over two years) and the Cowboys were punished to the tune of $10 million. An arbitrator dismissed grievances filed by the teams last spring.

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