Currently an umpire can impose an on-the-spot penalty if he believes that the condition of the ball has been unfairly altered.
But, Pakistan captain Inzamam-ul-Haq was found not guilty of ball-tampering charges yesterday by ICC chief referee Ranjan Madugalle because of insufficient evidence.
''Unless you see them actually tampering with the cricket ball I don't think there's a lot you can do about it,'' Bird told BBC News 24.
''I would bring that into that law. I wouldn't say you could do what you want with a cricket ball -- you could use a razor blade, a bottle top or anything then and that would be unfair.
''My hunch is you need to have concrete evidence to substantiate serious allegations,'' Bird, one of the most respected umpires of his times, said.
Madugalle made the not-guilty judgement on the charge laid against Inzamam during last month's fourth Test against England at the Oval.
At a subsequent news conference, when asked whether the law is now completely unenforceable without unambiguous video evidence, Madugalle said ''at this moment I don't know whether I can really answer in a concrete fashion.'' Meanwhile, former England captain Bob Willis said Inzamam escaped with a ''weak punishment'' at the ICC disciplinary hearing and the Pakistan captain's previous behaviour should have resulted in a stiffer sanction.
''Inzamam is a very lucky lad. Considering his previous record of appearances before the beak, he is very lucky indeed. It is a fairly weak punishment,'' Willis was quoted as saying by Daily Mail.