and it was just a matter of time before he would succumb. when i was doing this, i asked the people standing there, i said, hey. if you want to help, give me a hand. >> after more than a minute into taping, the woman capturing all this calls 911. >> i'm in the city of boston and there's a cop fighting a guy and he could sure use some backup. >> by that time, the eyewitnesss from the street grab all four limbs, while the sergeant handcuffs the man, who is later identified as ruben delgado. sergeant colombo, unharmed, then realizes the brawl's been caught on tape. the tape is invaluable. it's more than enough evidence for a judge to sentence delgado to a two-year prison term. as we've just seen, some people resist arrest by trying to fight off a police officer. other criminals try to fool cops with a good story. you've got to see this next encounter to believe it. listen closely and you be the judge.