Mariah Yeater's ex Robbie Powell is reportedly shopping his story -- which, if true, will take Justin Bieber off the hook for any paternal responsbilties (though Bieber seems pretty confident about that already).

Powell was previously implicated as baby Tristyn's father, after TMZ uncovered text messages from Yeater asking a friend to burn any paper trail leading to her ex:

Pleeease ERASE ALL MESSAGES from my mom where she says Tristyn is Robbie's son, one of the text messages reads. Ill kick u when we get paid..Im trusting you pleeease [sic]. The text signature is Mariah Laci (Laci is reportedly Mariah's middle name.)

The TMZ article included a screen shot of another text message, sent on Aug. 16. Would you please stress to Robbie how important it is for him to be in his son's life? Mariah appears to have written to her friend TMZ identified with the pseudonym John.

Powell reportedly has told friends that Yeater made up the story about her tryst with Bieber in an attempt to raise some cash, as many have previously suspected. Sources have told TMZ that Powell has been approached by multiple media outlets and is reviewing his options.

According to TMZ, Powell has no doubt he is the father of Yeater's baby and is eager to take a DNA test, as Bieber did last week. He wants to officially close the book because he's reportedly tired of Yeater using Tristyn to get media attention.

Bieber has already taken a DNA test to rule out paternity, though he was not legally required to do so. I just wanted everything to be out in the open, and be like, 'Listen, there's no reason for this to be a discussion,' Bieber said last Wednesday on The View.

An attorney for Yeater is not satisfied with Bieber's test, and wants him to take a second test to control for possible corruption. Jeffrey Leving told the New York Daily News that he and his client want to be present when Bieiber takes another test.

This case is unique in terms of media interest, celebrity and the amount of potential child support at issue, Leving told the Daily News. There could be motives on the parts of many different people to corrupt the evidence.

Bieber will need Yeater to provide Tristyn's DNA in order for the test to be conclusive. Results are still pending.