Last week we learned that David Cameron may have texted Rebekah Brooks "a dozen" times a day. Today, courtesy of News International's the Times (£), we learn of some of the contents. An updated version of Times journalist Francis Elliott and Independent journalist James Hanning's biography of the PM, Cameron: Practically a Conservative, reveals that Cameron texted Brooks in the week she resigned as chief executive of News International to tell her "to keep her head up" (not a direct quote).

In a revelation that will certainly brighten Labour's morning, we also learn that such contact then came to an "abrupt halt", with Cameron dispatching an emissary to explain that "Ed Miliband had him on the run." And there's more: Brooks and Cameron texted each other to make sure they were not seen together at the Heythrop point-to-point; Cameron asked the Met to open a review into the Madeleine McCann case in May 2011 as "a favour" for Brooks; and Royal courtiers warned that Buckingham Palace would "think poorly" of a decision to take Andy Coulson into Downing Street.

The case for the defence is put by Oliver Letwin. "If you are on the same side as her (Brooks), you have to see her every week," he explains. "This was how it worked." In other words, the PM courted Brooks no more or less than Tony Blair and Gordon Brown. But even if we accept Letwin's assurances, the problem for Cameron is that he was the one standing up when the music stopped.

It's tempting to dismiss the Leveson inquiry (before which Coulson will testify on Thursday, followed by Brooks on Friday) as of interest only to journalists but Rebekah Brooks's name is one that has penetrated the public consciousness. As I've written before, the claim that Cameron texted her a dozen times a day (more contact than most people have with their partner) could permanently reduce him in the eyes of the public. Conversely, as Sunder Katwala notes, there are "as of now, no actual texts/emails to/from Cameron to Rebekah Brooks yet in public domain." So long as this remains the case, No. 10 will hope that it can limit the damage.