HG: You can be convicted of most crimes upon the the testimony of one person, even if you deny it. Juries weigh the credibility of testimony and decide who's being truthful. Happens every day.
For example, would a police officer's testimony outweigh a ten-time crook's, that is, that if you were on a jury would you tend to believe the cop over the crook? I would, and I think I'm more biased against cops than the general population. Cops are just as willing to perjure themselves as crooks. But cops rarely lie about the actual crime being committed, and usually apprehend the right guy. And no matter what the claim here is, 99% of the time, if a case goes to court, the defendant did commit the crime and is just gambling.
If I were on a jury, asbsent any evidence whatsoever that a crime was committed other than the testimony of one party, especially an interested one, I would never, ever vote to convict the accused of a crime. Never.